Liminal
Lust
Liminal Lust is a hentai game set in a peaceful, upbeat and utopian world hosting a number of characters for you to meet and have sex with. It focuses on exploring and discovering random events that will play tricks on your expectations.
After naming your male character and selecting which genders you're attracted to, you go through an optional brief prologue and then appear inside a liminal space where you're tasked with finding weird anomalies and get rewarded with nanites.
While exploring, you'll often run into various characters you can talk to and ask them to have sex with you in exchange for the nanites you've collected. All interactions are completely optional.