f19, i pretended to have bad posture at the gym so that the hot girl helping me would keep touching my body to correct my posture

im very underweight so ive been having to go to the gym as well as eat healthy to try and gain weight and get healthy, the girl thats been helping me at the gym she is so hot shes super muscular and pretty, shes always getting on me about my posture and how its important while exercising and she puts her hand on my stomach and back to make me be in the correct posture, im such a loser i get so turned on from her touching me i keep purposfully having a bad posture and then i masturbate in my car thinking of her touching me. I feel so guilty after, shes so nice and helps me a ton and im just a loser perv.