Someone asked this question and i gave them a long ass explanation, i'll try to find it and copy paste it for you, i hope i can find it
I'll try to explain, in the end of chapter 20 and the start of chapter 21 there's a short haired psyche, while medea and helio got an invitation from the prince, both scenes are a glimpse from the future, start from chapter 21 until chapter 40 are flashback before psyche cut her hair short (psyche will cut her hair in the end of chapter 40)
So what happens in these 7 days flashback :
1. Medea was sick and kept getting nosebleeds in psyche's body because she fought the knights who tried to kill her at the birthday banquet.
2. Psyche wear nanny's necklace, helio got mad.
3. Psyche finally knew the truth about nanny, and the duke arranged her a marriage to king henel.
4. Psyche need to find helio and ask him how to face this problem, but helio has no answer.
5. Medea heard about word of god from the prince, and suddenly thought she has to find out what the word of god is about (she's afraid if it's mentioned her or psyche, and she also hoped that the word has a clue about how to get back to her original body).
6. Helio has a nightmare about death medea, while medea keep meeting death nanny in her dreams.
7. Red hair guy appear.
8. Medea sneak out to a bar one night and found out about her marriage arrangement with king henel, then medea ended up bump into red hair guy.
8. Psyche was desperate and didn't want to meet king henel, end up jumping off the balcony.
9. Medea suddenly choked on her tea and couldn't breathe, she thought it's because psyche's body is getting weaker again, she fainted.
10. Medea and psyche return to their original bodies even just for a few seconds. Then, medea is back to psyche's body that's already healthy, and psyche is back to medea's body that has wounded leg.
11. Psyche kept her wounded leg despite she could heal it, because she was chased by the servants so she can't use her healing power in front of them. Because of her wounded leg, she can avoid meeting with king henel.
12. Medea sneak out again, this time straight to the temple, she's wearing violet wig and seen by the prince.
13. The prince came to medea's house to prove that the violet haired girl he saw at the temple is medea, but he found psyche instead.
14. Helio and red hair are also in the temple, helio want to investigate about word of god for medea, and red hair want to announce his identity as cardinal.
15. The prince kiss psyche, psyche knew the truth about prince and got mad.
16. Helio met medea and talk about word of god.
17. Red hair is announced as cardinal and met the prince, after meeting the prince red hair see medea in the carriage and approach her.
That's what happens in 15 chapters around chapter 21-36 lol, cmiiw.
Found my explanation a month ago, i'm glad there are not many topics in this manhwa so it's still easy to find, just tell me if you want more explanation about chapter 37-40
I get the whole story but since chapter 22 I cant really grasp what happen idk if it’s the translation or the jumpy panel’s transition From one to one