The central theme of Heartstopper is the challenges of coming out and how someone with an attraction to people of the same sex comes to develop self-acceptance in a world of judgment and beratement. Charlie came out as gay to a couple of his friends 10 months prior to meeting Nick. Afterward, he experienced severe bullying for several months before some older children stopped it. Nick is not out as gay and is only just having feelings for a boy for the very first time. He is confused, unsure of himself, and he feels lost about what to do or how to proceed with his relationship with Charlie. Their shared attraction to one another, along with their different stages of self-acceptance, set the stage for how their bond unfolds.

When Charlie came out as gay, he did not really intend to. He told his friends, and word spread after that. Gossip led to bullying and name calling, which made Charlie feel alone and ashamed. Eventually, the bullying was put to an end by some older children, but Charlie continues to suffer the trauma of his experiences. It left him insecure about who he is, and he does not believe he is worth being complimented.