...incest...

[Playguuu]

MNGS-077 "I've been waiting for your return," said the father-in-law I hated so much when we finally reunited. He had turned into a stinky old man living in a garbage-filled room... He relentlessly r***ing me with his pent-up, abnormal sexual desire, cumming inside me repeatedly. He held me captive as his wife until I got pregnant as part of our family plan. Misono Waka​

No mother character in this one. But features pregnancy so that's a plus

 

[bigloser0]

These two show some promise:

PRPM-002 Intense Old Man x Sisters' Brainwashing: We are our new stepfather's sex toys. (Starring: Miyu Aizawa, Nanao Ayatsuki)​

Plot takes a darker tone, with more fucked up scenarios.

PRED-894 My mother is infatuated with a scumbag. I'm being forced to help her with it. - Yuna Hinata​

Featuring the ever cute Yuna Hinata.
Both feature mindbreak.

prefer the 2nd title
first title the actresses' breasts looks fake to me