[Triple_R]

Generally speaking, a major protagonist needs to be likable or entertaining. They can certainly be both, of course, but they really should be at least one or the other. Kirino is very much a case of the character (hopefully) being entertaining to make up for her lack of likability. Basically, you either get the humor of the character, or she won't resonate with you because it's really hard to feel sympathetic towards a character with her personality drawbacks (barring some sort of really effective tear-jerking background story, of course).

Thankfully, I found Kirino pretty amusing this episode. The following quote is a big reason why...

Originally Posted by Lunar Archivist

On the other hand, the way this episode poked fun at some of the, shall we say, excesses that some of the more extremist otaku out there engage in was absolutely hilarious.

When this anime decides to gently poke fun at some otaku excesses, this anime is very amusing, and so is Kirino by extension. Because most of us get those excesses, coming into contact with them regularly as anime fans.

But when this anime decides to laud and justify the otaku subculture, it goes from comedy to drama, and Kirino's lack of likability then becomes an issue. In other words, it gets in the way of us sympathizing more with her (an important element to effective drama is getting the audience to truly care about the main protagonists).

Basically, Kirino is a tsundere that's too tsun and not enough dere, as others have noted. If this anime wants to be more than pure amusing comedy, then it should make Kirino more likable, or at least give a good reason for why she is the way that she is. Because let's face it, there's not much to like about her when she isn't amusing you.