The humor comes from the unexpected and slightly absurd comparison, combined with the relatable scenario of enjoying food while perhaps wishing for social interaction. The friend's reaction validates the joke.
Summary
The creator is in a car with a friend, holding a burrito. He makes a joke about wishing he was with his friend instead of the burrito, which his friend finds amusing.
Structure
1Creator holding a burrito in a car
2Creator makes a joke about the burrito
3Friend reacts with laughter
4Creator comments on friend's reaction
Transcript
If you know when your neck deep in a burrito but you wish you were fucking your homeboy instead. What the fuck, bro? You're teasing a little hard, bro.