Complex sentence: As he regains his lost memories, he sacrifices the immortality bestowed upon him by the celestial robe to save Aya and his children (Miku and Aki).
Split into simpler sentences: As he regains his lost memories, he sacrifices the immortality bestowed upon him by the celestial robe to save Aya. He is determined to protect Aya and his children (Miku and Aki).