Cricket gg7’s right. It’s フフン Fu-Fun not つつン tsu-tsun. Nevertheless, thanks for the chapter
Editops, sir flimflam already addressed this and much better than I . ガンッ Those three smileys are quite the struggle シ (shi), ツ (tsu) , ッ ( chiisai tsu)
@DarkEboreus Yeah, I came here just to say that. The author wasn't making up Sfx. Unfortunately, the TL probably just doesn't have enough experience to know what they're supposed to be. It wasn't "Gantz." It was "Gan" with a small "tsu" in order to show the level of shock. That "tsu" isn't pronounced.
It's cool, though. It just comes with experience TLing.
TL notes are fine because it's very difficult to preserve the nuances through the translation, but since some readers are bothered by it, it might be better to put it as a footnote
e.g. small text bottom of page, or an extra page at the end of the chapter