Complex sentence: Later in the manga, it is shown that the reason for this is that Outer Moka is a fake personality in her rosary created by Akasha, and the purpose of Outer Moka is to protect the seal and her body while Inner Moka is asleep.
Split into simpler sentences: Later in the manga, it is shown that the reason for this is that Outer Moka is a fake personality in her rosary created by Akasha. The purpose of Outer Moka is to protect the seal and her body while Inner Moka is asleep.