I'm so glad that you've given both Severus and Rosmerta some comfort in their lives. That scene of their bittersweet last night is particularly effective; I like the fact that despite his bleakness and bitterness, Snape can still offer some tenderness and care. I have no doubt that when Rosmerta eventually learns the truth about him, she will not be ashamed at all.
Then they both forgot the war, and bad decisions, and the ache of losing people they loved. Tonight he was going to forget the future. Great line.
Taste and smell, they were a Potion Master's most acute senses Yes!
Finally, she kissed him and it felt like a promise, one he was unable to keep. *sniff*