Sonoa gets drunk and ends up living at Tachibanakan. Yuu gets everyone to have a welcome party for Sonoa, so they meet by the riverside in appropriate outfits. Yuu has water guns waiting for them, and has everyone enter a "Water Gun Survival Game".
Kono-chan!
Kono-chan!
¡Kono!
¡Kono!
Kono !
Kono!
Kono-chan!