While Riki and Saya are walking through the dungeon, Riki is reminded of the fact that he was in love with Saya. However, Saya interrupts his thoughts, saying that he distracts him. At that moment, she trips and falls down.
Saya tells they need to pull a rope to advance to the next level; however the rope is located to high to reach. So Saya needs to stand on Riki and jump in order to pull the rope. However they also need to defeat a gigantic golem in order to advance to the next level. While Saya is distracting the golem; Riki is trying to find a way to defeat it. Riki finds a sword, and taunts the golem to attack him. Saya climbs on the golem's head; and finds a key-hole on top of its head. Riki throws the sword to Saya, who inserts it into the keyhole, which destroys the golem. However, Saya falls down and hurts her leg. Riki carries her to the next floor.
秘宝を探して迷宮を探索している理樹と沙耶は、地下５階に足を踏み入れた。沙耶の正体は謎のままだったが、いつしか理樹は彼女を愛おしく思うようになっていた。だが、なんとなくいい雰囲気になったふたりの前に、巨大な動く石像が立ちはだかる！ 沙耶は銃を抜き、理樹は知恵を絞って攻略法を考える。次々と出現するトラップ。その先には一体何が待っているのだろうか？ 最終決戦の場が近づきつつあった——。
