koi(恋) and ai (愛)
Yuuki directly admits that she had been harboring romantic feelings for Kaname. However, the English translation renders 恋してた as “in love with,” which flattens the nuance of 恋してた and isn’t entirely accurate.
“恋してた”(koi shiteta) comes directly from koi (恋):
koi(恋) → koi suru(恋する) → koi shiteru(恋している) → koi shiteta(恋してた)
and Why Hino Matsuri chose that specific wording when Yuuki first confesses to Kaname, especially when there are so many different ways in Japanese to express romantic feeling?
To avoid any misreading or distortion of her feelings for Kaname: when she says her heart was split in two, it reflects how both emotions were still koi (恋)—simple, unformed, not yet fully matured into something heavier.
Only later, after Kaname’s Memory Arc, does that feeling slowly deepen into ai (愛), becoming more complex, more irreversible. So she names their child Ai Kuran, because koi (恋) is no longer enough to hold what her feelings for Kaname have become.
