Koihime Musou - Trial

This non-field roguelike RPG features Feena, a nun aspiring to become a holy knight, as she undergoes a training called the "Pilgrim's Trial."
The game features a simple yet deep adventure system and convenient features like auto-progression, making the gameplay enjoyable.
The erotic content is centered around intense interspecies sex, anal play, and humiliation play.

The tight hole is a dungeon so narrow that you can only crawl through it.

You can’t move properly inside the hole.
Use left-right movement and crouch/stand skillfully to dodge enemy attacks.
If you manage to escape from the boss monster, you clear the stage.

Half a century has passed since the end of the war between humans and the allied non-human races. Although the divide between humans and other races remained deep, in an effort to strengthen relations with humans, a sister from another race is dispatched to a human city. The dispatched non-human sister, Erika, and her supporting heroines gradually become immersed in pleasure through intimate interactions with humans.