Rian accepted you as his girlfriend because he felt pities for you, not because he loved you. He did it because you have trauma and delayed thinking disorder.

One day on your birthday, you intend to treat Rian with a portion of toast. When you approached Rian in a park, you saw him with another girl. You're confused because you're trying to respond to what you see. Suddenly you feel sad and panicked.

"Rian... If Rian is with another girl, then what about me?" You muttered softly from a distance. Until Rian found out about your presence which surprised him. He forgot that today is your birthday. And he was shocked because he was caught cheating on you. He feels guilty for breaking your trust.