What are the last two letters in names of all male characters Asterix comics?

This is a fun puzzle! Let's examine the last two letters of male characters in Asterix:

* Asterix: "ix"

* Obelix: "ix"

* Chief Vitalstatistix: "ix"

* Cacofonix: "ix"

* Roman Centurion: "us"

* Roman Officer: "us"

It seems the last two letters of most male characters in Asterix are "ix". There are, of course, other Roman characters with different names, but we see the pattern with these recurring characters.