Peter Grill and Bathing Etiquette (ピーター・グリルと入浴の作法, Pītā Guriru to Nyūyoku no Sahō) is the 4th episode of Peter Grill and the Philosopher's Time anime series.
After saving Luvelia, Peter takes a bath and gets a golden opportunity with Luvelia, however the elven curse falls upon him.
The Great Worm Goblin is about to violate Luvelia, however Peter arrives in time and frees her. Angry, he faces the goblin and kills him with ease, making the other warriors cheer his name. The ogresses are observing the battle and get even more excited about their desire to get his genes.
Later, Peter takes a bath and recalls how villagers thanked him for killing the creature as it was a problem for them, however he can't figure out why he has a boner. He wonders is Vegan has something to do with it and she appears confirming it. She explains its a forbidden curse "The Eternal Erection", however having it for too long will cause permanent damage and inability to get hard again. Peter begs her to remove the curse and Vegan explains the only the dispel it and that is to release his "juices" inside of her. Peter still refuses stating that Luvelia is the only woman for him. In that moment, Luvelia hears Peter's voice and realizes he is in the nearby room. She wonders if he knows the legends about this particular hot spring and as he doesn't, she explains that according to rumors those who soak in the hot spring will be blessed with children. Luvelia asks Peter if he would join her and test the rumors. Peter wants to join her as he never had progressed beyond holding hands with her, but due to Vegan's curse, he ends up explaining that he can't join Luvelia at the moment.
Having no choice, Peter gets on his knees and begs Vegan to break his curse. She happily agrees and they get in bed. In the morning Peter is depressed on what he did.