The series starts off with no profanity at all.
Minor language like "Hell", "Damn", "Piss", "Ass", and "Crap". Very mild and infrequent and it didn't have any and much offensive words.
Mostly uses of "heck", "darn", "dang" and "suck".
There was one time when Natsu said "Son of a-", but someone else said something else before he could finish what he was gonna say.
Natsu got called a dumbass once.
"Ass" is ocaissionally used.
"S*icide" is used alot.
Mild, nothing moderate.
No vulgar language. Only minor, non-offensive words like "Damn", "Crap", etc. Nothing serious.
Language is spread out and used infrequently.