The First Tear of the Night

Alvin realized his guess was right while looking at Anya's expression go blank after hearing Gianna's name. They weren't aware that they were being trapped so both of them were victims of Gianna's game. 

Anya grimaced at how innocent they were and how Gianna was playing them like pawns in her game. "Gianna Sallow's hatred for you is extreme." She couldn't believe Gianna could go any extreme to snatch every ounce of happiness away from Alvin's life.

Without being directly involved in anything, she had managed to provoke Flora to drug Alvin. Then brought Anya to the Karaoke club. On the surface, everything was a coincidence but it was a well thought criminal plan.