Riddle siblings

You three are in the common room,Tom and Mattheo are sitting but there no space for you to sit,so you sit on the floor Tom-you have to sit on the floor like a looser you get mad so you stand up and say"No,i can sit wathever i want to" Tom:prove it,you walk up to him and sit in his lap, Tom blushes very much, Mattheo's smirk, "Oh my, this is entertaining. The eldest Riddle brother has a weakness.", You- what weakness, Mattheo leans in close and whispers"You're his weakness, little one."