Generally speaking, almost any crazy ecchi scenario Rito gets into (mostly without even lifting a finger). Like the times Mikan opens the door to Rito's room, sees him in a compromising position with whichever member of his Accidental Harem snuck into his bed at the time, and then hastily apologizes for interrupting before shutting the door.
Rito: Why do I have to put up with this shit in the morning...
Yui Kotegawa's debut chapter starts with her trying to rein in Lala's antics. Unfortunately for her, she starts by telling Lala to get rid of her tail, thinking it's just a weird fashion accessory. This prompts Risa and Mio to demonstrate that Lala is an alien by molesting the tail (and giving us the page picture for Fantastic Arousal in the process), Ren shows up and starts fighting with Rito, and when Yui breaks it up Ren sneezes and turns into Run, who glomps him in her now ill-fitting male uniform, and Rito makes a break for it only to run smack-dab into Lala, knocking Peke off her head and making all her clothing disappear. Welcome to the life of RitoYuuki, Kotegawa, hope you stocked up on antacid because it'sjust gonna keep getting better!
The gang is trapped in an RPG simulation which is beginning to collapse. Since their clothing is digital too, it starts to disappear along with the castle they're in. Kotegawa tells Rito not to look at the girls, only for the poor guy's pants to disappear right as she's looking at him.
At the end of the chapter, everyone has been returned to the real world. The only problem is that Saki, her Girl Posse, Run, and the Principal were all dumped inside the Amazon.