Yuno heard the whole conversation, thanks to the small recorder that can connect to his laptop or smartphone. He is listening with his earphones because Asta is in his room. So that it can be heard clearly because Asta has been noisy. Asta is playing a RPG game with his friends, Klaus and Luck. During the game, Asta screamed to himself in frustration. It made Yuno annoyed because he can't listen to Y/n's conversation with her parents properly. Luckily it's been recorded, he can hear it anytime he wants. Why doesn't Y/n realize there is a small recorder inside her school bag? Because she doesn't really take care of her school bag. So she just left the small recorder in her bag.
Now, Yuno needs to make a plan. Because Y/n's parents made Y/n feel sad, he can't forgive him. He won't let people who made Y/n sad stay alive. But on the other hand, he knows Y/n's father is a mafia boss, it will be quite difficult. Forced, he must need Langris's help. He need to take the small recorder first from Y/n's bag.