to Yasunori Sakuta. In regards to your apparent difficulties adding in the cut girls to DOAXVV (ie, Tina, Mila, Rachel, Christie and Lisa), I can offer some suggestions regarding how to overcome those troubles. You mentioned in particular that one problem is how to reconcile established backstories to have the girls actually like the Owner, citing in particular Leifang's canonical love interest in the form of Jann Lee as one reason. However, the other cut girls don't actually have any love interests.
Tina and Lisa certainly don't have any love interests as far as I know, with her interactions with Zack being platonic so far as I can tell (especially when Xtreme 3's ending for Helena implies that if anything, he might be in a relationship with her, or at the very least she's firmly aware of his feelings for her).
Mila merely has a fangirl crush on Bass Armstrong, and while she does have some interactions with Diego, there's nothing canonically pointing to either of them being romantically interested in each other.
Rachel does have a large degree of respect for Ryu Hayabusa in her home series of Ninja Gaiden and DOA5, but it's implied to be more of a camaraderie type of respect than romantic, like with Momiji, especially when canonically, Ryu Hayabusa is romantically involved with Irene Lew.
Lastly, regarding Christie, I don't really recall her ever having any romantic interests in anyone. She certainly didn't with Rig Donovan, viewing her more as a client, and if anything, both Dead or Alive Dimensions and Dead or Alive 4 strongly implied she'd turn against Donovan if given the opportunity. And as far as Rig, she's more of his handler, or rather, his trigger than an actual romantic partner. Probably the closest she has to any love interests is Eliot, and even there, it's mostly one-sided with him, as she herself is more affable to him than actually romantically interested in him.
To put it simply, it's actually a lot easier to add in the rest of the cut girls than it is to add Leifang due to them lacking any canonical love interests, at least, any love interests that they themselves have to someone else.
Besides, let's not forget that Hitomi has a canonical love interest as well in the form of Ein/Hayate, and she's included without problems even if she did technically appear in DOAX3 beforehand.
Regarding backstories in general, eh, I can think up of a couple of ways to add them in without it conflicting with the owner even without canon love interests. The main point of the festivals are about a celebration of a woman's beauty and strength, right? Well, simply use that for the various girls overall. I know Momiji and Hitomi at least were hesitant to join initially because of issues regarding beauty, so Rachel could be allowed to have that same issue as well, maybe Mila, since they're not the types to focus on beauty.
In fact, I can probably give a couple of ways for having them want to join the Festival, heck, even fall for the Owner if needs be.
For Tina, maybe have her decide to join the festival and win it because she sees it as a stepping stone for whatever new dream she has (could be Governor, could be something else since DOA6 implied she gave that one up due to being legally too young to run for office). Maybe gain some genuine respect for the Owner during this time and admit to possibly wanting to become a wife to him after gaining her dream.
For Mila, maybe have her focus more on the strength bit a little more, though still show some interest in beauty as required, maybe have some uncertainty about the beauty elements, like Hitomi in her story mode, or to an extent Momiji in her story mode. Maybe even have Tina's presence be a motivating factor for her going to the island as well, since she's a Tina fangirl. As far as falling with the Owner, maybe have her develop some respect for the Owner for taking her under his wing, maybe also teaching her that sometimes beauty doesn't hamper fighting.
For Rachel, like I said, probably have her join despite not really caring too much about beauty per-se because, aside from needing to hone her Fiend-hunting skills, she also wants to also enhance her beauty because she wants to further ensure she does not succumb to her cursed blood, still being affected by how Alma let her Fiend blood corrupt her and being forced alongside Ryu Hayabusa to take her out. As far as the Owner, maybe have her be slightly shy around him, mostly because he's the first person besides Momiji and Ryu that she's actually interacted with, and maybe have her eventually relax around him and realize maybe there's a bit more to life than being on the run from her cursed blood.
For Lisa, she could go to the island for essentially the same reason why Ayane and Helena went to the island: Namely, investigate a possible conspiracy that's going on at the island. Maybe also have some scientific curiosity regarding the beauty and strength bit. And as far as her interactions with the Owner, maybe give her a similar arc to Helena, where she is open to the Owner, but in a classy way.
And finally, for Christie, basically have her go to the Venus Islands for the same reason as Ayane and Helena: Investigate a conspiracy on behalf of MIST (assuming that's still around in the game anyway), or even just go there as part of a job of possibly targeting the Owner (whether it be for Donovan or someone unrelated to him is up to you), but after meeting with him and learning of the Venus Festival and it dealing with beauty and strength, she decides to spare him for the time being under the condition that she participate in the festival for her own ends, while toying with the idea of killing the Owner after the festival concludes. Oh, and maybe have her develop genuine feelings for the Owner throughout her character episodes to the extent that she comes close to having second thoughts regarding killing him. That would be a fairly unique way of handling a potential Owner romance, plus it's a fairly common trope where someone who intended to kill a person ends up falling in love with them. A good example of it is Mara Jade and her falling for Luke Skywalker in the pre-Disney Expanded Universe materials for Star Wars despite initially intending to kill him as part of Palpatine's final command, or maybe Ivana Humpalot from Austin Powers: The Spy Who Shagged Me, who was dispatched by Dr. Evil to kill Austin and lure him into a trap, but after playing chess with him, ended up just wanting to have sex with him and forgoing the operation due to infatuation.
And heck, to throw in added incentive, I can even cite ways the cut girls can have interactions via the girls already in the game, stuff that if anything would aid tremendously in their backstories. For example, with Tina Armstrong, she could have a friendly rivalry with Tamaki due to the both of them having been former fashion models. Since Honoka according to Famitsu is a huge Tina fangirl, she could also interact with Tina as well as Mila, even engage in a friendly rivalry with the latter regarding fangirling Tina. Plus, since Honoka's an established pro-gamer, it would also help to bring about an obscure aspect about how Tina herself is a gamer, maybe have her give Honoka a serious edge on that front. For Rachel, aside from obviously interacting with Momiji, she could also have a somewhat awkward interaction with Nyotengu and Kanna due to her status as a Fiend hunter, and yet having to tolerate a Tengu and an Oni as her vacation guests. Lisa, aside from bonding with Mila and Tina, and possibly also Helena, could also end up interacting with and befriending Misaki as well, since both did technically serve the same roles in their debut games. Maybe also bond with Luna and Sayuri as well, largely because of the former's scholar elements, and the latter's a nurse. And heck, maybe also have her bond with Honoka due to being curious about her copycat nature due to her scientific background. Even Christie might have one way she can interact with the girls. For one thing, maybe have Marie Rose and Christie interact, especially when both technically worked for Helena at some point, and would be nice to see how the former and current servants interact. Granted, Marie Rose would definitely be wary of her due to the events of DOA6 if they are to be referenced, but then again, she was wary of Tamaki, and that really didn't stop them from interacting. And due to Luna's similarities physically to Christie, maybe have them interact as well. And that's just a handful of examples I could come up with at a given time. Who knows, maybe you'll come up with even more ways for the cut girls to interact with the rest of the cast.
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