DLSite product summary:

The woman he adored turned out to be the mother of his friend! By chance he became his lover, and the mature woman teaches him about the sexual pleasure.
She is very proactive! Wherever and whenever she is, she feels like it!
And the naive boy goes deeply into sex with initiation from this older woman.
Depending on your choice, their relationship changes…

Characters
Midori Mikoshiba (voiced by Aoi Hongo): the mother of Takashi.
Kazuki: Takashi’s friend.

13 CG base images, 84 total incl. variations
Over 640 spoken lines, fully voiced woman
A robust scenario over 160kb in text
CG mode / event mode / hands-free mode
1024x768 screen size

DLSite link

Downloaded originally from OppaiTime
Now that OT is dead I’m not sure this is available anywhere else so before I delete this from my system thought that maybe I should upload here to give someone else a chance to archive this.

VirusTotal scan of the game .exe file here
They all look like clear false positives and I ran this years ago without any issues but you do you.