escalation_hardcore
Escalation ~Aoi Houyou~ is a visual novel with sexual content developed by Melody and released on 1999. The english translated game, Escalation ~Hard Core~ was released on 2002, with a further DVD released on 2006.
It's part of the Escalation series which is connected to the anime Cream Lemon.
VNDB entry: https://vndb.org/v3133