Several years ago Kevin Smith claimed on his podcasts that his anal fissure was from reading on the toilet for extended periods. One instance he mentioned it was at this performance https://en.wikipedia.org/wiki/Sold_Out:_A_Threevening_with_K...

The first result for 'anal fissure toilet' appears to back this up

>The following are tips for preventing an anal fissure:

>Straining - avoid straining and sitting on the toilet for a long time.

https://www.medicalnewstoday.com/articles/186514.php#prevent...