Stan
来自Big Physics
early 21st century: with allusion to the 2000 song ‘Stan’ by the American rapper Eminem, about an obsessed fan.
wiktionary
From Stan(“Stanley”), after the song Stan by Eminem (2000), [1] a fictitious account of the rapper's encounter with an overly obsessive fan named Stan. Sometimes assumed to be a blend of stalker + fan, but perhaps simply chosen for the rhyme. [2]
Back-formation from -stan