Source: https://e-hentai.org/g/3463486/021e51d532/
Original title: オチをたずねて幻想郷3 | Romaji: Ochi wo Tazunete Gensoukyou 3

A collection of 4komas mainly featuring the cast from Double Dealing Character to Wily Beast and Weakest Creature.

Volume 1: pool #28624
Volume 2: pool #28728