One of the more direct interpretations is that, shinji(protagonist) is so deprived of love, that he would do anything to have any kind of proximity to someone else.

I also like to interpret this as a criticism to the creep evangelion fans who would to the same thing giving the chance, which he later says "I am so fucked up". The whole movie had a lot of criticism towards fans who even sent death threats to the creator after the previous ending.

The series talks a lot of about problems caused by lonely, and several characters represent different form to deal with it. Sometimes it show this things directly sometimes it uses allegories, and a lot is up for interpretation.

Evangelion is one of the animes with the most depth I've watched, but I didn't get it on the first time I watched, this movie specifically is really dense.