Upon receiving an invitation to a treasure hunt from the famous mysterious item artist Reinette, Ramune and Kuro visit Reinette's mansion. There they encounter Ayame and Nico, who have also come to participate in the treasure hunt. However, when Ramune sees the man with them, his expression freezes, and he attempts to flee the scene. That man is Ramune's master Momiji!
The more keys a person gathers, the more 
they believe that act must have meaning.
.كلّما جمع المرء مفاتيح، آمن أنّ ذلك الفعل يحمل دلالةً
Je mehr Schlüssel jemand sammelt,
En les rassemblant,
Più chiavi una persona raccoglie, 
più si convince che l'azione abbia un significato.
Quanto mais chaves coletam, mais as pessoas
acreditam que há uma razão para tal,
Чем больше ключей собирает человек,