The poem is just two short lines, but they hold a surprising amount of feeling. The speaker is asking someone to wake them up "before you see the last of me." The "you" seems to be leaving, or perhaps the speaker is the one who will vanish from view. Either way, the speaker doesn't want to sleep through the final moment. They want to be awake for the goodbye.
What stands out is how quiet and small the request is. There's no drama, no pleading speech, only a plain wish not to miss the ending. That plainness makes it touching. The phrase "the last of me" can be read in more than one way: a last glimpse of a person walking away, or something larger, like the end of a life. The poem doesn't say which, and that openness is part of its power.
The mood is tender and a little sad, but also calm. The speaker accepts that an ending is coming and asks only to meet it consciously.