During a season two episode, while observing the target, a bishounen male model, Ren says the model isn't as good looking as him. He then starts posing in a mirror...only to get busted by Wanyudo.
There was also that one episode near the beginning of season one where Ren posed as a "male escort" and one of the episodes after that in which he was hit on by a male lingerie salesperson.
Specifically, the episode where Ren poses as a "male escort" is episode 6 of season one. He does it to set up the "banishment mind rape" for a woman who was committing adultery (the target) who framed an innocent neighbor for adultery by having the neighbor be raped (the client is the neighbor's daughter, taking revenge on her mother's behalf). Then, in the "banishment mind rape", the adulterer's husband catches her in the act and starts verbally abusing her...and then, for another crowning moment of funny, replaces Ren underneath the adulterer.
During another season one episode, he got hit on by a drunk guy he was trying to get information from.
Ren and Hone Onna's behavior during the season one, episode 7 "banishment mind rape" is hilarious to watch. The target is a bitchy actress-to-be who arranged for thugs to rob her rival of her voice. At the start of the punishment, the actress is put on stage to put on a play where she repents for her sins. But every time the actress tries to apologize, her "true feelings" show up in the form of a female monster talking out of her body crowing that her rival had it coming. The funny part is that Ren behaves like a heckler in the audience, complaining that he's just not getting the emotion and the play won't be good until the actress speaks from her heart. Meanwhile, Hone Onna behaves as a hard-to-please critic who wonders what godawful play she's forced to be watching. This stops being funny around the time that kabuki stagehands break the actress's arms...
The "banishment mind rape" in season one, episode 9, is actually pretty funny at the beginning. The target is a corrupt baker who stole the secret recipe of a pair of twin sisters, and then made it look like the twin sisters stole the recipe from him. At the start of his punishment, he serves desserts to customers but the desserts all taste horrible, and the customers start throwing the desserts at him. Watching him pathetically cry that it's not really his recipe, while in the middle of a "food fight," is hilarious. Of course, it stops being funny when the next part of the punishment is making him part of the cake...
Several of the banishments in season three are pretty silly.
Case in point: Episode 3's antagonist, Shimatani, an utterly cruel neighbor who tried everything in her power to get rid of a little girl's dog, including poisoning the poor thing and sending the little girl off a balcony, is dealt with in hilarious fashion. She's dressed up in the manner of a comedic Super Robot villain and her mecha is whacked with a stick by a dog-mecha piloted by Ren. Then she's pelted with garbage bags by Hone Onna's dog-mecha, then with cistern water delivered by another dog-mech. When her mech is destroyed and she tries to berate them, nothing comes out of her mouth but dog barks, a punishment that doesn't abate even when Ai (who has adorable dog-ears for this scene) ferries her to Hell.
There's also one that parodies westerns. The victim gets stuck in a turtle shell and is shot at by the minions in an exaggerated manner (Wanyudo turning around between shots, Yamawaro with Guns Akimbo) followed by Kikuri breaking out a rocket launcher.
In the fifteenth episode of season two, Kikuri folds a airplane out of a newspaper and lets it go with much glee. Into the head of Enma Ai. Who proceeds to make some slight changes and throws it into the air.