VotedforKodos

Personally, I know next to nothing about those 3, other than that Meltlilith is losing feeling in her hands.
First post suggests that Sakura is living with Shirou at the Emiya mansion, while he goes and sees Rin outside and at her house. It sounds like it was flat-out "Shirou goes to Rin and Sakura's school after leaving his, goes to archery to wait for Sakura, it's her turn to clean up so they wait around and she fucks him once she thinks everyone is gone."
For training, given that Reinforcement and Projection are the only things he can do, something like giving him stuff to Reinforce and doing things to distract him, like rubbing his dick or masturbating herself. If he fails, then he gets punished. Punishments might scale: first time, he has to watch her masturbate and isn't allowed to do anything else but watch; second time, a little more sadistic footjob than normal; third time, she sits on his face until she cums. By the time he fails a fourth time, she's suspecting he's doing it on purpose (he's not; just super not talented) and ups the ante by peeing in his mouth. What she wears could start out at first as her school uniform or regular outfit, then move on to the lingerie after a few sessions when she realizes what a pain it is to have to wash those every time.