The struggle bar mechanic is rather common for these ryona games, I think they are called at least. A few of the other ones I like are the Unholy series (Unholy Sanctuary, Jail, Disaster, etc), the Koonsoft games (Witch Girl, Angel Girl, Kung-fu Girl etc)
A common one people will tell you about is Night of Revenge
there is also Alien Queen Eve
Rose and the Magical Beast I like the animations of even if the gameplay is a bit basic
You can look here for more:
https://f95zone.to/threads/ryona-humiliation-game-collection.138900/
honestly, non of these is quiet like sinisistar, to me there is something special about this game. The dark brooding atmosphere makes it feel like a souls game turned hentai. (in fact Bloodborn deals with a lot of the same themes as the 2nd sini does, with eldritch gods hoping to procreate through humans)
But for a good hentai experience, there is a lot of nice stuff on that list.