Are you also against M/F or are you ok with that? Because maybe you could add arousal traps that force men to engage with the woman? Or other such scenes. M/M would be loved, but i am ok with M/F too. After all, i do love the game so far, and i like woman too even if i prefer M/M. lol.
Just thought it would be a good idea to include the men somehow and if you dont want them affected by the grapplevines because of M/M then why not add things like other traps that makes them interact with the woman? or make a trap that leaves the player vulnerable to them. And so on.
Just some ideas, it is your game and even if it is purely focused on tentacles and woman i would still love it. The game itself is also quite fun so that is good too. (ps, currently the mana crystals feel a bit useless to me. Maybe a change there is required?)