Obligent
After shitting your pants, you wipe your butt and accidentally get some poop on your hand, and then you smell it because you feel obligated to.
After I took a big dump, I wiped and smelled my hand like I was checking my own sh! t for quality control.
I wiped my butt and smelled my hand like it was my duty.
After I took a dump, I wiped and then smelled my hand because I felt like I had to.