Had an idea for Urshifu where it starts off as Kubfu, since the personality is determined by how she trained then, who cant decide which path to take, Dark or water, so the MC gives the option to learn SEX FU style by having her train by the other legends and use Dialga's time ability's to make her go through a training montage while the MC travels up to a peak for the showdown battle. This part is a little complex where Kubfu has not evolved yet but Dialga would allow her to change temporarily into the evolved form for the fight. The MC would use the strategy of making her horny to win and show the way it can be used. She returns to being a Kubfu but is ready to take this path knowing she will get pregnant but she likes this path that blends the dark and water (mostly water) fighting style together to be flexible (to be able to get a massive belly) and use some darker style attacks, one can be called (BALL CRUSHER) hence the dark evil type of the move used on those she hates. Once she sees the MC as the grand master of SEX FU and then have sex which is the first time she has experienced this and just before her orgasm the MC pulls on her ribbons to make it an explosive experience that make her understand the potential and thus she then evolves into Urshifu while he is still in her to continue training with the MC and build up this new fighting style for her kind and kids.
Also With the idea of MC Having sex with Nebby to evolve into Solgaleo/Lunala while in them would effect his dito DNA to change in his dick to start making the energy Necrozma wants but at double the production since he was in both of them when evolving and Necrozma would not be able to take him over like the two thus he could have some defense against her for final battle and overpowers her. A latter boat scene can be Necrozma fuses with one of them willingly to have a sort of threesome with the MC.
Also had an idea for Darkrai where the MC asks Manaphy to allow her to experience the pleasure of anal from Lugia by sharing the emotions and let Lugia know what darkrai feels when having anal.