Eunha confessed her love for both of them. & she said didn't wanna make any rash decision which she'll regrate latter, before she got shot by witch's sister. After getting shot by elder witch she started to forget her memory then she said "i love you"
to Hunter.
One phrases that repeated more & more was BEING BY HER SIDE it's vague term & again it was intentional. It's inside massage or phrase between Enuha & Witch. which Hunter clearly doesn't understand when witch said the same thing to her.
In the end Eunha came to witch & tell her that she'll be her side that she promised her. means Eunha & Witch are going to be wifu & Hunter remain as BFF.
Witch is so deep rooted in Eunha's heart that her personalty changed after forgetting that witch. Hunter realized that, the person she loves is the person who ones fallen (or still maybe) for a witch. without witch, Eunha is not the person that hunter loves.
Moreover bond between Hunter & her dead GF is greater than the bond between Hunter & Eunha. meanwhile Eunha & witch togather spend hard times & share years of pain so naturally their bond is more stronger than you can imagine.
that's why Eunhs said (in the end, last chapter 55) that she'll be her side to that witch.
Witch wanted to be bridge between Eunha & Hunter But in the end Hunter ended up being as bridge. & because of Hunter they both mate with eatch other. It was Hunter who sends Eunha into witch's subconscious,
it was a metaphor. that's why timeline is messed up in last panels.
It takes time to me ))))
She forgot just one thing: that she already loved the witch before she drank elixir. And last medicine helped her to remember this fact! And she came to her witch to reunoin with her - because the witch was the one she ever loved!!!