The speaker of "Innocent Bystander" watches someone being tormented by a group and can't bring themselves to step in. The short, broken lines make the poem feel hesitant, as if the speaker keeps starting to act and then stopping. They tell themselves they never join in the abuse, yet that excuse doesn't bring much comfort. They admit they don't even like the victim, which makes their guilt more complicated and more honest.
The feeling that runs through the poem is regret mixed with self-deception. The speaker notices the sadness in the other person's eyes and sees how hard they try to fit in, while the bullies notice nothing. The promise to help "next time" appears more than once, ending with "once again," which suggests it has been made before and broken before. That repetition gives the poem a quiet, uneasy mood. Being kind in your head, it implies, isn't the same as acting.