To test her out, ask her if I can hug her.

If my guess was correct and Miki Nikaidou was never in a relationship, she probably never had intimate contact with anyone. I thought for a while and walked in front of her, opening my arms.
[player]Nikaidou, could you give me a hug?
Miki Nikaidou squinted her eyes and looked at me with caution. She hesitated and stayed away.
[Miki Nikaidou]Why asking for a hug all of a sudden?
[player]Do you not like it?
[Miki Nikaidou]I don't mind hugging, but that's something you only do to people you like. Don't you mind, PLAYER?
[player]Not at all. Because I like you a lot, Nikaidou.
Miki Nikaidou didn't reply. Instead, she stared at me for a moment, as if she was trying to identify whether I meant it or not.
Suddenly, she moved over and gave me a gentle hug.
[Miki Nikaidou]I like you too, PLAYER.
Her tone sounded teasing as usual but was slightly trembling. I never thought the calm, intelligent Miki Nikaidou could have such a lovely side. Like a butterfly that just left her cocoon, she was awkwardly trying to expand her wings.
I patted her gently on the back. I'm so fortunate to be the only one seeing this side of her.