Vague Game Description by White Masq:
A text-based horror H-game set in an unsuspecting hospital, and with FMV H-scenes. You play as a patient who awakes every night to find the hospital becoming a hellish place--only wake up the next morning and seeing that everything seems normal again. You find out that the bizarre world you visit is called “Mirage”, and that both you and a fellow patient travel there every night. There are those amongst the hospital staff who are trying to tap into this realm; it’s up to you to find out exactly who, and what you’re going to do about it.