Knightess Cecily’s NTR Corruption (女騎士セシリー寝取られ堕ちる)

Cecily is a royal knightess who is engaged to be married to alchemist Ray.
She is ordered by the king to complete an exploration mission together with him, however, their boat is assaulted by monsters during the journey, and they wash up on an island full of criminals.

Ray’s leg is injured, so it’s up to Cecily to find a means of escape from this island.
The criminals are all lusting for her though…