[That hand on Aidan's sleeve seems to have been slippery because it slid right up around his neck to better hold on. Falling would be bad after all. You never know when falls could happen. Best to guard against them.
Also, this kissing back might be coming more eagerly. Yuuri is still largely inexperienced, but he's still a teenage boy and maybe kissing isn't as icky as it seemed a few years back.]