The prospect of crawling in directly atop her was not a thoroughly unpleasant one, but Severus decided to be good and merely squeeze in beside Lily, as she had suggested. Before he tried, however, he pulled his wand briefly to cast some charms to reinforce the cords holding the hammock up, as well as the hammock itself. It looked sturdy enough to hold the both of them, but he didn't want to find out the hard way that it wasn't.
Actually getting in was a bit awkward, because the last thing he wanted to do was elbow her or some such, but he finally managed it. Once he was more or less settled, Severus raised the arm closest to her, in the hopes that Lily would cuddle against him. Though he supposed if she didn't want to, the worst that would happen was he'd look a bit foolish. If she did want to cuddle again, however, it would be more than worth the risk.