Sometimes “Sean” is spelled “Mare”

I was going to claim that this tattoo was mine, but Satan’s French manicure gives it away. Trish had some new work done last week, but unfortunately the tattoo artist thought she said “Mare” when she said “Sean”. I myself don’t have any tats, but if I were to get one it would look like this, which is why I don’t have any tattoos. …
SOTD: Cali’s next governor?
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I forgot the riddle yesterday. Dammit. Here it is. RIDDLE OF THE WEEK:

Explain how 2 can equal 1?