Complex sentence: When her time of birth finally came, Michel seized his chance and absorbed Seira into his body, and her birth was therefore delayed until Lucia can retrieve all the pieces of her heart contained in Michel's feathers.
Split into simpler sentences: When her time of birth finally came, Michel seized his chance and absorbed Seira into his body. Her birth was therefore delayed until Lucia can retrieve all the pieces of her heart contained in Michel's feathers.