Having so bluntly stated that they aren't friends all of a sudden didn't seem like the best answer ever. Her [i]obviously fake[/i] hurt expression did sting a bit, but both girls seemed enough aloof for him to realize that no real damage has been inflicted. "Ah, practicality - that makes perfect sense." Nero briefly added to her statement about outfits, although his wasn't exactly practical, rather than a fashion statement. 

[i]"Social statement,"[/i] he swiftly corrected his own narrator. 

"Sui Sanada, Nishiki Kalemoru - nice to meet both of you." He nodded yet again, not saying anything to imply his unsigned squad status. The worst thing that could happen was if Nishiki tried to get him to join Squad Eleven. And considering how open she is, he wasn't going to count that possibility out. The thought made him shudder. 

Seeing how the two interacted with each other actually made the atmosphere feel comfortable. A thought even crossed Nero's mind that he would be able to get used to their antics, however loud they may be. That's when he noticed a hand coming towards his hair. He didn't even register the question until after noticing the hand. 

Actually. The atmosphere wasn't that comfortable. Those are the kind of antics that go over any sane line. "No!" He moved back, flipping his hair dramatically. "If you touch my hair, I'll..." he wanted to say 'kill you', but wasn't really comfortable saying that to a girl he just met. That's when Nishiki joined the fray, practically demanding to touch it. The excited expression on her face was too much to bear. There was only one way out of this. "What do I get in return?" 

No sane person would actually go forward with this and offer something in return. It was a fail-proof question to get him out of the predicament of other people touching his hair.