Season 1

The one-of-a-kind prototype of Holo falls into Han So-yeon's solitary life, eager to help with anything she needs — if she will allow him.

Seeing she has a crush on her co-worker, Holo offers to be So-yeon's dating coach. Ko Nan-do monitors their growing bond from his lab.

Nan-do moves in next door to So-yeon, convinced that being with her has broken Holo, and determined to do whatever it takes to fix him.

Conflicted about her feelings, So-yeon tries to distance herself from Holo. Baek Chan-sung sends his men after her glasses.

When So-yeon wakes up in the hospital, something's changed about how she sees Holo. He and Ko Yoo-jin urge Nan-do to reveal himself to her.

So-yeon realizes that loving Holo means certain relationship norms are out of their reach. Nan-do deals with unwanted attention from the police.

In danger from those attempting to steal the prototype, So-yeon agrees to stay at the lab. Nan-do puts on his best impression of Holo.