The series' rapid-fire Lovecraft references and meta-comedy don't skip a beat even in a throwaway hot springs episode. Nyaruko's relentless flirting and the cast's chemistry carry what could've been forgettable fanservice into genuinely funny territory. Fifteen minutes is all it needs to remind you why you loved this show in the first place.
Mahiro and his otherworldly houseguests escape to a secluded hot spring resort for what should be a relaxing getaway. Instead, the trip becomes a chaotic showcase of Nyaruko's shameless flirting, Cuuko's competitive antics, and Hastur's brooding presence all cramped into close quarters. Steamy encounters and comedic misunderstandings pile up as the characters navigate swimwear, bathing scenes, and the intimate atmosphere that hot springs naturally invite. The OVA leans hard into ecchi humor while maintaining the absurdist energy the series is known for, treating fan service as just another tool for comedy rather than the main event. What emerges is pure comedic chaos where supernatural beings act far less dignified than their cosmic horror origins might suggest. This works best if you're already comfortable with the franchise's particular brand of rapid-fire gags, self-aware lewdness, and the way it refuses to take romance or propriety seriously for even a moment. It's lightweight entertainment designed to make fans laugh through embarrassment and ridiculous situations.