Boy, Friskie's got a knack for creating threads that can take off at full blast, ain't she? Its barely 30 mins and 27 replies already.
Well, Jiro(u) is already a name in japanese, It means Ji (second/2) rou (son). A family who had a second boy, may give him the name of JIRO(U). We say it as JIRO in english, but they say it as JIROU in japanese accent.
There are no L's in the jp alphabet, so all L's are substituted as R's. Also the format of the name is important. so JILLIO in english would be equivalent to JIRIOu (small u) or something like that in JP.
There's no offical meaning behind the name of JIRIOU, but there is meaning for the prefix (JIRI-) for those that would choose it.
ji (letter of first meaning)
of that person; oneself
ri (letter of second meaning)
advantage; profit; profit
ji (letter of second meaning)
business; fact; matter; possibly; reason; thing;
ri (letter of second meaning)
arrangement; justice; logic, reason; truth
There's other meanings for Jiro's jirou, if combined as one word however: