Denim advice?

Hi everyone! Just a question on denim, my friend has blown a little butthole into each butt of his jeans, and has asked me for help. Unfortunately, I’ve never really worked on denim before, and he doesn’t have any donor denim he can sacrifice. Not sure if he’d be okay with a little appliqué in between his cheeks, but I have some blue embroidery thread that I can “blend in”.

What techniques does everyone think I should do? Something for strength mainly as I’m doing 2 pairs so it’s a reoccurring problem for him.

Thankyou!