If you’re not a big Instagram user, you might ask “Sean Who?” – but with more than 1 million followers on Instagram, 21-year-old Sean O’Donnell is a big social media star.

Your next question might be – why should I care? Oh you will care, once you see his abs. There you go:

1. The thing with the shirt

2. Just sitting there

3. Nice arms, too!

4. The mandatory Calvins shot

I, think about my next meal in #mycalvins

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5. Pool time

6. Some more fun at the pool

Not a bad way to start off the week☀️

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7. Short shorts

8. Bathroom selfie time

9. His captions are amusing

10. You have to work for your abs

11. Doing that thing with the shirt again

12. Chilling

Sunday mood.🌹

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13. Over and out