Complex sentence: Long in love with the unconscious Asseylum, Slaine grieves her silently and agrees to marry Princess Lemrina; upon Asseylum's reawakening, his frustration and despair corrupts his personality, and he changes from a peaceful, kind young man into a war-hungry militarist.
Split into simpler sentences: Long in love with Asseylum, Slaine grieves her silently and agrees to marry Princess Lemrina. Upon Asseylum's reawakening, his frustration and despair corrupts his personality and he changes from being a peaceful, kind young man into a war-hungry militarist.