Complex sentence: Hiyori is the lost spirit of a girl who in life loved Yuya deeply however, she died though before she could confess her feelings and thus cannot reach the gates of heaven and obtain eternal peace.
Split into simpler sentences: Hiyori is the lost spirit of a girl who in life loved Yuya deeply. Hiyori died though before she could confess her feelings and thus cannot reach the gates of heaven and obtain eternal peace.