Yeah but other players could still attack and kill what you have tagged, and it will re-spawn eventually. In FFXI all enemies bind to you in a way where nobody else can touch it unless they're in your PT or you call for help.
Thus you can stand there with a named mob on you forever if you'd like and never kill it and it would never re-spawn unless two were allowed at the same time to up, which some were.
I did this on occasion just being silly with useless NMs in lower lvl zones, where the NM couldn't hurt me and just ran around with it on me...hehe
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