http://omaris-sister.blogspot.com/2010/02/wild-ones-arakure-volume-9-is-out-from.htmlHere’s Arakure chapter 46.

Link to Arakure Chp 46

So … I don’t want to give away what happens, but there’s significance in Japanese culture about what name you call a person by and it comes into play in this chapter.  People are called by their first name only by family and really close friends.  It is basically a sign of intimacy.   Therefore, when the person you like calls you by your first name, it’s a big deal and escalates the relationship.  In the Viz version of the manga, Sachie calls Igarashi “Rakuto” from the start, whereas in the Japanese version she always calls him “Igarashi-san.”  I don’t know how Viz is going to resolve the error.  I’m surprised they went with “Rakuto” in the first place considering the cultural significance of it all.  I guess we’ll see when Volume 9 comes out sometime next year.