‘…then couldn’t shake off the two burning rings.’
This relates to the idea that the act was, in fact, a ‘butterfingered’ proposal from the character. This displays the poet’s view that the emotions of love and pain are intertwined.
In the 13-year-old’s mind, branding the subject of their love with rings on their fingers—albeit the wrong ones—was ensuring that they could never lose his love, which would stand for eternity. He ensured that she was branded, with a symbol of his love forever.
React!