Maybe it's beacuse of Byul's hands.

Dependable hands that are always ready to calm her down whenever she's nervous. How Byul's hand plays with her own hand to distract her from those negative thoughts. How the younger girl's fingers perfectly entwines with her own and swings their hands happily together. How a  thumb would caress her holded hand while they are walking towards an unknown destination. And how those dependable hands make every insecurities disappear.

That's what Yongsun thinks. Maybe it is the younger girl's hand.

Soft hands that caress her face like it's the most precious thing in this world. How a hand would run through her hair, fixing it or tucking it behind her ear. How those soft hands would massage her aching bacķ and her aching neck, whenever the reality of being old hits her on those parts. How those hands pat her head, making her easily fall asleep whenever horror movies keep her from closing her eyes. And how those soft hands makes her feel special whenever they're on her.

Yes. It's definitely the blonde girl's hands

Strong hands that shove her down their shared bed. How those hands roam around her body, making her feel hot and bothered. How a hand would play with her in the most enjoyable way possible while the other hand would caress her face. How those hands would slowly and painfully go down, down to the place where Yongsun's explicit arousal is. How those hands pleasure her, making her moan Byul's name endlessly, slowly, harshly, until she screams in pure ecstasy. And how those strong hands pull her towards the younger girl's body while whispering 'i love you's to her ear.

Yes. Yongsun firmly believes that it is definitely Byul's hands that make her fall in love all over again for the greasy hamster