Ok. The amount of crap said her is seriously starting to piss me off so I need to say something. First of all, this wasn't fanservice. Fanservice is when it is used only to please fans. In shown like this it become kinda distorted, but in general scenes with bouncing boobs for the sake of bouncing boobs is fan service, illusion of rape isn't. Sure, you can say it was just shown for the sake of showing men grouping Mirei boobs. It was a mental attack, attack that was supposed to shaken Mirei so she won't be able to defend herself. Making girl (lesbian at it) experience rape is probably the worse and best one at the same time. Mirei blushed after her breasted was exposed. Typical girl's reaction in any other anime, About dropping fluid. Yes, it was her vaginal fluids. Why it makes perfect sense? Because that is how girl's body work. When body is being stimulated and brain's realize there is going to be intercourse, it starts to product vaginal fluid. It doesn't mean girl is ok with it and wants more. It means body is preserving itself and reading for eventual insertion to avoid damage. It happens even during rape, granted body has enough time (rapist just insert straight away, there is no chance for preparation). Illusion men doesn't force themself into Mirei right away, they group her breasts and kiss her. They give her body enough stimulation that she indeed started to get wet. Pointless scene? Only fanservice? Mirei is able to break illusion because she experienced hell in real life suggesting that either she indeed was raped in that second episode flashback or worse. If anything that entire scene shown me other side of Mirei I didn't see and it was badass.
Mamori doesn't deserve Mirei cos she flock to Akira on the sight? We don't even know if she is lesbian, but seriously it is perfectly fitting behavior for her considering what happened so far. She was normal 16-teen that was suddenly thrown into some isolated island away from home she knew, all her family and friends. She is totally helpless and clues. Mirei just happened to shown right next to her and chose to protect her. So far Mirei is doing everything in her own accord. She even gave herself up so no one will suffer without consulting Mamori and ignoring her complains. Just because Mirei decided to protect Mamori so far it doesn't mean Mamori is indebted in any way. Even if she should show some gratitude (and she did) that doesn't oblige her to fall for Mirei or even return her feelings. Even if Mamori is lesbian/bi she most likely isn't aware of it. I'm ready to bet she was rose in typical het is default environment and loving a girl didn't even cross her mind before. She dreamed of prince on white hours for crying out loud. How more stereotypic we can get? So I can totally understand that after being thrown into middle of this entire chaos she completely don't understand once she saw her actual prince on white horse she would be immediately charmed by him. Her deepest dream came true in all this madness? Of course she will devote herself to it, to stay sane. Mirei is cool but it wasn't what she dreamed about all those years.
As the side not I found her entire obsession with Akira hilarious. It was first time since I watch VD that I actually laughed. Also Mirei reactions were priceless. It again confirms her as 100% lesbian also building on her character more (which she didn't have that much except for being cool so far). Mirei loves/is charmed by Mamori but knows that she can't force herself. She might be displeased with Mamori's obsession with Akira, but she won't voice it, cos she knows Mamori owns her nothing. She is free to choose whoever she wants and Mirei can't tell her she can't choose Akira (at least until she gets jealous enough).
About Akira. It is totally obvious there is a reason she cross-dress and we just don't know everything yet, but it isn't a big secret from audience so they don't try to hide it. Voice actresses confirmed all mine characters will be female for god's sake. Obvious reason that first come to mind is that it is all show for girls so they won't go insane here. Sure they don't have to hook with other girls, but some wants to have some male idol, even if they can't have him, just so they can copy with all this stuff. Akira is promoted as this awesome only male so they have someone to fawn about. Akira has clearly some contact with Onee-chan as well as bigger relationship with Kasumi. All 3 of them seems to actually work together to keep everything in peace while maintaining a illusion that they try to force everyone to follow their rules. Charlotto seems to be the actual villain or more like kind of person that cares only about herself as we see with her disobeying order and being unsatisfied she couldn't punish everyone. At the end of episode we see either Akira being affected by some possible side effects of w/e power she has or maybe her sister/twin sister. Maybe ability to shapeshift? but it would be really crappy shapeshifting. Or maybe sister has some incurable sickness that is why they are in such rush to get away from it.
Or maybe I'm just giving this show too much credit. But you clearly give too little.