She’s saw every single dick pic you’ve ever received.
Only she understands when you say, “I saw my husband today” and that you are referring to the hot guy that has no clue that you exist.
Teasing each other with no mercy. Like when you admit that you’ve been listening to Bieber’s album on repeat (even though you know everyone secretly loves it). Or when she gets diarrhea before a big date.
Cause friends are nice to each other, but best friends are total assholes to each other.
But she’s also the only one who literally bail you out of jail, pick up Pepto-Bismol for you, beat up fuckboy, make you laugh no matter how shitty you feel, and can’t imagine living without you because you’re actually her sister and she’s yours.