He doesn't like the way you drink tea.

Brahms being British and coming from a more wealthy background he was more traditional.

He was most familiar with the expensive bitter leaves. Ones that had exceptional flavor but he wouldn't dare put any sugar or much of anything in it when he drank.

So when he say you doing different things with your tea, like adding sugar honey and lemons or creamer and pearls he scrunched his nose. His deep voice spoke.

"What are you doing, love ♡?"*