Vlerk, whose real name is Edmond Spierts, is a comic artist from Groningen. He initially worked under the penname Inktvis-Prutduktie, but eventually started using Vlerk. He attended the Art Academy Minerva in Groningen, and is one of the editors of the comics collective/magazine Gr'nn since 1996. He has also published his work in Wordt Vervolgd, Titanic, De Toestand, Zone 5300 and Stripburger.
Sherpa published his solo book 'Vleermuizenissen' (1993) and 'Nabije ontmoetingen van de vleermuisorde' (2006), and he also contributed to collective works like 'Tussen de rails' (1989), 'Signed by War' (AWA Foundation, 1994), 'Formaline' (1995), 'The Earwax Museum' (1995) and 'The Sperminator' (AWA Foundation, 1996). Vlerk also designs posters for Poppodium Vera.