I’ll beetle you up!

Dear Maggot (Margaret),

Your peasant (pleasant) attitude (gratitude) makes me feel lonely (lovely) when I am around you.

You are such a horrific (terrific) person!

Next time we meet, I wish to punch (lunch) you. I'll give a you a good clout (shout).

Jeers (cheers) to you,

Robert

P.S. as a real-life example, I had a manager who once sent a colleague a message thanking them for their selfishness (selflessness).