According to a course at memrise.com, 저는 롭이에요 means I'm Rob (humble). I am wondering why Rob is translated as 롭이 instead of 로비. To me, the latter seems to be more natural and is easier to write.
In the given Korean sentence, Rob corresponds to 롭, not 롭이.
The closest transliteration of the English name Rob /rob/ [ɹ̠ɒb] would be 롭 /rob/ [ɾop̚] according to Korean phonology and phonetics (and also the ROK government standard). 롭이/로비 would sound /robi/ [ɾobi], with a completely unnecessary [i].
The sentence "저는 롭이에요" is decomposed into