He posted on the discussion website explaining how his girlfriend had gone vegan for health reasons - claiming it had cleared her skin - but said he was tired of eating plant-based and needed 'some mac and cheese with cut up hot dogs'.
'Doing it for her own good'
"I thought I would prove to her that the whole 'dairy gives me acne' thing is in her head," the post - titled Today I F***d (TIFU) up by accidentally giving my girlfriend acne - reads.
"For the past two months, I've been emptying the same soy creamer container and filling it with dairy creamer. I was gonna do a big reveal, like 'Surprise! You can eat whatever you want!' But she's been wearing makeup both in and out of the house lately…and last night I saw her barefaced for the first time in a while and it is BAD. Like insects about to hatch out of her face bad."
He added: "I feel bad but on the other hand I was doing it for her own good!"
'Please never do that again'
The post has caused controversy online, with one person writing: "The TIFU isn't that you gave your de facto acne, it's that you massively betrayed her trust because you think you know what is good for her better than she does. You're not just an a*****e, you're actually a bit of a monster since you still haven't realized this."
While another user commented: "You also could have made her horrendously sick! If she's been vegan for years and you gave her animal products then she could have gotten extremely ill. Please never do that again."