The speaker lives inside a bubble and insists it doesn't bother them. It is their shelter: clear, cool, and protective, even if the glass is "smutty" and the surface "oily splotched." Outside, other people, the "dry misfits," drift past without noticing. The speaker watches them and presses their lips against the bubble's skin, a gesture that feels part curiosity, part longing, part detachment.
The tone is calm and a little defensive. Saying the bubble "doesn't trouble" them, and that what others do "isn't troubling either," sounds like someone repeating a comfort. The last lines tilt the mood. Keeping the bubble up takes work, and "the air's not free here." Judging by the imagery, the poem suggests that isolation feels safe but has a cost. The result is a quiet, slightly uneasy picture of someone who protects themselves by staying apart, and who may not be as content as they claim.