Suggestions apart from ones related to sex are indeed a tall order. To that end, here are some that come to mind as potential candidates:
Saiin Jutsushi by
Yoriu Mushi is an absolute classic (in my book at least) that focuses far more on the act of hypnosis than any other manga I can remember reading.
Mesmerism by
Saikawa Yusa / abgrund is another great one, though it definitely goes heavier on the sex.
Sanbun Kyoden has done a number of stories that feature hypnosis as the core plot element, with
Readiness and
Maso-Mess being my favorites.
Hoshino Ryuichi is a similar artist with some hypnosis-heavy tales, though the endings trend darker.
Saimin Choukyou Gakuen is the main one, with
Sennyu Tsuma Satomi Kiroku being another possibility.
Saimin Stream by
aeni9ma is an... experience, that you may wish to experience.
And finally, if you want to branch out from manga into the 3D render space, I've got a (mainly Pixiv) link thread with various sorts of long-form suggestions, some relevant, some not so much.
forum #99526It's hard to say how many of those will be to your liking, if any. Hopefully a few will though~