AIO for thinking my dad is a creep?

So, I am not sure if ts the right place to put this but I have literally nobody to tell this to. Nobody. So, me (19f) have noticed that the living room walls, right next to the couch, have semen stains. A lot of them. And ik that they are those kinds of stains cause my bf (now ex) accidentaly shot his load on the wall of the bedroom and it looked the same (I cleaned it). I live with my dad and my step-mom. I tried to ignore the stains on the wall, cause I wasn't sure how to even bring it up. But then, today I noticed dried cum all over the TV while watching some show. I'm not exaggerating. It's revolting, disgusting. And its obviously from my dad. And it makes my skin crawl like just watching fucking tv. It's nasty. I didn't tell my stepmother. It's disturbing asf and I honestly think my dad is a creep. Who tf would leave jizz stains all over the house, especially on the TV, while you have your daughter at home? Am I wrong for thinking this? Am I overreacting? Is this fucling normal?