Ah Fat (a.k.a Derek) pulled Kuan Ching away and they started arguing on the streets. Coincidentally, Constance met them. Luckily, Kenny lied. He said that Kuan Ching and him were a couple and were fighting, Ah Fat came to be the peacemaker. Constance believed him.
(At this scene, Constance was linking arms with Ah Fat and she asked him to call her? It sounds like they are already dating, but they are not o.O)
Constance is afraid of a dog (it's chained up). It barks at her. She was frightened and ran into Ah Fat.
They ate dinner at a restaurant. Turns out that Ah Fat purposely waited for her to finish her class to pick her up but he was late. Ah Fat gives her flowers and a heart-shaped ring. He asks her to be his girlfriend, but she rejects.