Complex sentence: Seventeen months later, Rukia, now lieutenant of 13th Division, returns to aid in restoring Ichigo's Soul Reaper powers and engages Riruka Dokugamine, one of the people that have stolen Ichigo's own powers.
Split into simpler sentences: Seventeen months later, Rukia, now lieutenant of 13th Division, returns to aid in restoring Ichigo's Soul Reaper powers. She then engages Riruka Dokugamine, one of the people that have stolen Ichigo's own powers.