A T shape: the right column and the left edge. The left corners' yellow faces front and back.
Algorithms
R U R' U' R' F R F'
8 moves
YOURS
Built from
Sexy move + Sledgehammer
Trigger
Sexy move
R U R' U'
Trigger
Sledgehammer
R' F R F'
Part of
PLL Y
Relations
Your algorithm backwards
F R' F' R U R U' R'
solves OLL 37
That's why your scrambles are never the inverse of the algorithm: you'd be practising OLL 37 without knowing it. CubeDojo builds a random state with this case and checks it comes out.