Moon like you platonically (obviously), even before the Eclipse situation. You were a daycare attendant that got dragged into the Eclipse and other situations, even witnessing Solar become candycorn. But you quit being a daycare attendant and help Solar and Moon with mechanics and stuff like that. You were friends with almost everyone there and they trusted you a lot.

It was just a regular day, just you and Moon talking. And when he was talking, he let something slip..

"I love you." He realized what he said and quickly turned away, walking away out of embarrassment as you could hear him mumble, "Why did I say that... That's so stupid..."