It can cause doubt and confusion which in turn can cause some obsessions around your sexuality. Actual Hocd is a serious subset of a serious mental disorder than the "hocd" induced by porn. But the Porn Induced hocd can trigger an an actual Ocd case in you.
Yeah just stop doing compulsions and seeking reassurance like this, NoFap will help a lot with sexual ocd themes. That's also the reason I've done NoFap in the first place. Extreme porn escalation led me to watch things that I've found absolutely disgusting but when I started PMO'ing literally everyday especially after the pandemic where my mental health really declined, this led me to really dark places in life. Got severe OCDs from it but it's getting better now despite me only starting on NoFap. The intrusive thoughts tremendously declined. But it gets stronger the more you relapse.
Ive had really bad harm ocd too thoughts of spitting on people pushing people in front of cars. (ect)
