Always happy to see more Succubus releases! Great ending though. She says she hates sex and Succubi, but I think after what happened with her Senpai...I'm sure she'll learn to love it, especially when she's with him. Great ending though! So it looks like she really did enjoy herself with him, and I think it could signal the beginning of a nice relationship between the both of them. Also how nice of her sister to be her wingwoman, helping her get her Senpai.
Mayu would likely get used to the succubus life, with the right (a-hem) "motivation", and looks like Tsuyoshi-senpai (lucky bastard) fits the bill just right.