(Dedicated to all prisoners)
I’ll send you all my love, in a letter, sealed with a kiss
Abbreviation: Sealed with a loving kiss
In the days of snail mail, young people and prisoners would write a letter, kiss the envelope and write SWALK on the back.
Snail - Ślimak, Snail mail - term for traditional post
And here's one of the greatest, classic, British comedies; the prison based 'Porridge' with some advice for lovelorn Lenny.