When I was trying to write his name I was too lazy to load up the series page to double check. lol all i did was watch the part where he said his full name a couple times over.
So its Lelouch for sure... but... ranperuuji...taking what the makers considered L's instead of R's... Lanpeluji... mmmm Lanpeloush? Lanpeluge?
Well basically I guess its "Le"-"Lew""shu" ... "Lan""Pe" "Ruuji" Like how Strike "Rouge"(Ruuju) is said... close to like how "luge"(Ryuju) (the sport) sounds. Just at the end its "ji" instead of "ju".
(Lelouch Lanpelouji) I guess.... lol
JP and their katakana usage and whatever they come up in English for it is insane... and defies common sense very often. lol