Ep. 12: Peek a Boo members dive at Miyakojima, then host a chaotic Otori party with Spirytus and alcohol mishaps.

Peek a Boo gathers at Miyakojima for deep-sea diving. Iori, who missed his exam due to illness, remains in shallow water and faces teasing from Kohei. Chisa stays on the boat to comfort Iori, who suffers from seasickness but expresses enjoyment of the activity. Later, after the group is banned from their restaurant, Shinji and Ryujiro organize an Otori party in the hotel using a large pot of mixed alcohol. Everyone adds Spirytus, and although Iori and Kohei initially resist, they eventually drink. Aina accompanies a nearly naked Iori to retrieve more supplies and complains about his attire. Azusa offers Aina a drink, but she accidentally consumes a potent beverage that alters her personality, causing her to frighten Iori and Kohei into fleeing. The two reflect on their diving club experiences while Aina pursues them.
Episodes
- Ep. 8 · Shinji offers part-time moving work to Iori and Kohei who spend earnings on bar tabs before attempting bartending.
- Ep. 9 · Iori and Kohei organize a mixer involving Chisa and a King's Game with Peek a Boo members.
- Ep. 10 · Peek a Boo arrives in Okinawa for a trip involving beach activities and diving exams.
- Ep. 11 · Iori practices diving with Chisa while misunderstanding leads to his illness and Azusa's drunken confession
- Ep. 12 · Peek a Boo members dive at Miyakojima, then host a chaotic Otori party with Spirytus and alcohol mishaps.