as someone who's actually experienced being the object of codependency, this either isn't really it, or it's really mild. all of that wanting approval from others and wanting to feel needed is pretty normal psychology; what's abnormal about codependency is the extent, i.e. when it begins to harm everything else about a person's life. 99% of the time in manga, codependency as used by the layman is just any relationship that is "abnormal", with normality defined by the majority looking on from outside the actual experience of codependency, rather than whether or not it's actually impeding the individual's ability to function on a daily basis (which we don't usually see in a manga because manga tends to focus on just one aspect of life). this one is slightly better because 8man gets to evaluate for himself whether his behavior is abnormal, but he's also kind of assuming the worst of himself, and you can see this in how he's evaluating what implications codependency has for his character rather than his wellbeing. i think what was mentioned about "playing a social role" (which is also pretty normal psychology) is a better fit with what he's doing than codependency. as an aside, though, just because some behavior is the result of "normal psychology" doesn't mean you shouldn't change it. it just means you have to evaluate that for yourself with some healthy introspection.