When Harry swiped the little black book that had been slipped into Ginny's cauldron, he hadn't expected to gain a big brother. But Tom has his own secrets, secrets that could help the wizarding world - or destroy it.

(Aka the Tomalongadingdong™ fic) It was a normal day for Harry. He woke up, made breakfast for his relatives, ate some leftovers, and went out to do the chores set for him. Then it all changed when he accidentally disturbed a snake in the grass. Please do not message me about translations. I'm not accepting them.