Likely a Mandarin transliteration of 'Lestat' (the vampire in Anne Rice's 《
吸血鬼编年史》 / The Vampire Chronicles) or a similar Western name like 'Leister'.
勒 lè handles 'le-',
士 shì handles '-st-',
达 dá handles '-tat / -ter'. Other Lestat renderings exist (
莱斯特,
莱斯塔特), so
勒士达 is one of several competing transliterations.