Complex sentence: It is shown that Rinne and Prism Queen Amou June are messengers from the Prism World who bring the Prism Sparkle to different worlds, however the latter stayed on Earth for too long that she began to disintegrate and lose the Prism Sparkle almost completely.
Split into simpler sentences: It is shown that Rinne and former Prism Queen June Amou are messengers from the Prism World who bring the Prism Sparkle to different worlds. However, Rinne stayed on Earth for too long that she began to disintegrate and lose the Prism Sparkle almost completely.