I'm not sure if it's love, trust, or the potential of finding food, but I have four guppies that seem like they love me. No matter what I am doing, such as gravel vacuuming, doing water changes, rearranging decorations, trimming/pruning plants, or feeding, they like to swim around my hand and arms and nibble on me and whatever I am holding. They trust me far too much, as I am clumsy, and have accidentally whacked them with hoses and plants before. Yet they still trust me.
By the way, I love your loach!