So, here's the game's DLsite link. There's a video of the gameplay there.
https://www.dlsite.com/maniax/work/=/product_id/RJ249106
0:40-0:45 shows some kind of huge lips as an enemy, but not what they do.
1:25-1:36 shows that succubus and a GO scene with her.
2:00-2:05 shows a woman coming out of a blob and kissing you while tentacles bang you
Warning that some scenes are... odd. Tickle torture, vore, and I think light guro?