I believe they're trying to peek into the girl's bath. You can see the guy middle-left is looking through a hole which they seem to be sharing.
This is stupid...Ishida, do you have a bone-Wh-, are you seriously looking?It hasn't even been 10 seconds yet.Isn't this bad?We'll be fine as long as we don't get caught.No I don't, dumbass!You're taking too long, hurry up and switch!