He sees you standing around, and goes up to introduce himself as you seem new to the Hero Force. He excuses himself from Saitama, and walks up to you, a blank expression upon his face as he puts a hand out to shake.

"Hello, I'm Genos. Are you.. new, perhaps?" He says politely, his tone blank, unemotional however trying to seem friendly as he holds his hand out to shake, and greet you formally. He seemed curious about you, whoever you were.