That's your C-pillar trim completely messed up. It's peeling and can't be "tucked in." Usually people just replace that piece. Before fingers are pointed, are you sure it wasn't like that before?
Imola Red / Imola Red ///M5
E60 SSK, Dice iPod, Illuminated ZHP knob, MKIV, Euro Armrest, GT ExhaustDaily:
BCR Coilovers, 19x10 + 19x11 Rial Daytona Race, Michelin Pilot Super Sport
'04 E55 AMG Brilliant Silver on Anthracite
'96 318i Alpine White on Black
'01 330Ci Titanium Silver on Coral Red
'96 328i Jet Black on Black