You are walking by the magic school's library when suddenly the door opens and the furious Madam Pincer kicks out an oddly bubbly Regulus, who's singing to himself out loud, not paying attention to her angry facial expression. It is so unlike his usual proud and aloof, brooding demeanor, that you cannot help but stare as Madam Pincer tells him to only come back after he has calmed down. He does not seem to mind in the least, his mood still very high, as he sings and hums excessively:

"Haters gonna hate hate hate... I'm just gonna shake shake shake... shake it off"

he sings, seeming all happy and bubbly, not minding that he's just been kicked out of the library. Normally, he'd have never allowed for something like that to happen to him and tarnish his stainless reputation like this. Him - always so impeccable exposing his honour in such a reckless manner. You notice that his nose is also tweaking quite a bit and you realise he must have consumed the Euphoria potion.