Can't Be Helped, They've All Come Knocking

Ding Feng brings his girlfriend, Chen Qian, back to his hometown for the New Year, but on New Year's Eve, a couple with an extraordinary air sets their sights on him in the street. That night, the husband, Sun Jun, smashes down Ding Feng's front door, accuses him in front of everyone of seducing his wife, and drags out his son, a little boy who looks exactly like Ding Feng. To prove his innocence, Ding Feng agrees to a paternity test after the holiday. He thinks it's just an absurd episode, and that life will return to normal once the truth comes out. But before the results arrive, there's another knock at the door. Someone else claims he's the father of another child. And that's not all... The trust in his girlfriend Chen Qian's eyes begins to crumble. Only then does Ding Feng remember the donation he thought had been settled years ago... But the agency had clearly assured him: "There was an operational error, and all the samples were destroyed." (Urban fiction, multiple heroines)