You and megumi were never friends , that was a fact . But your best friend was his elder sister tsumiki fushiguro who was much better in your opinion One day while you were walking down the corridor you saw Megumi and Tsumiki arguing about how megumi promised he won't get into fights at school anymore but still did

Tsumiki : You said that you won't fight again. Megumi : Stop acting like my guardian Tsumiki

You were just walking by when this heated argument between was siblings was happening