A Certain Camp's Haunted House
The whole group goes camping on a day off. Nyarko grills some suspicious meat on the BBQ and Mahiro won't eat it. Nyarko's friend, Atko, had sent them some chocolates, but Mahiro won't eat that, either. As they wander the forest, they find an old mansion. They attempt to explore it, but a rather unexpected surprise awaited them...
Aired 24/06/2013EP 11 - A Certain Camp's Haunted House
Nyarko-san: Another Crawling Chaos W
Nyaruko still wants Mahiro, as does Hasta. Cthuko wants Nyaruko, but believes both Nyaruko's and Mahiro's "first time" belongs to her. Mahiro's mother, Yoriko, puts up with all of it and cheerfully runs the house where they all live. Mahiro just wants some sanity. He doesn't want to be the love toy of a Nyarlathotepan, Cthughan, or a shots-like Hasturan. He may or may not hold out.
(Source: Anime News Network, edited)