That much Toshi could do, along with with pushing himself up on his left arm - it could support his full weight easily, he just couldn't use it to shift himself much. He knew Souji could probably lift him by himself - he could vaguely recall being half-carried into the apartment, one arm around Souji's shoulders - but that would have been a little embarassing, particularly now that he was mostly lucid. And weight aside, the difference in size made it a little awkward