Look at this S! Cupid's Prank - Vol. 4 Ch. 37 - Night of Sex

[MangaDex]

 

[etriuswimbleton]

Good point. Makoto's Mom COULD have been under the effect. but maybe shes strong enough to tolerate it to when she gone into menopause stage the feeling was gone? That and maybe Rin's Birthmark power at that age is very low.