Yeah, he's gunning on Severus not planning on murdering him or turning him in. Which is a gamble but he realized he was walking into a trap box before he entered. It's a better chance than gambling on never getting caught on his own.

Anyway, while he waits he's going to make some tea. There's a nervous energy about him even with his spine rail-straight and his hair tied back perfectly neat and tidy and his robes in perfect order and basically he's the perfect pure-blood wizard that's waiting for the gallows Severus Snape.

So: drinking tea.