The phrase refers to content focused on interactions with unrealistic size differences, typically in an SFW fashion. As the name implies, these interactions usually happen with a giant character, and a tiny character, though ordinary human-sized characters are generally accepted in the mix.
churchhurt is where you experience a degree of distance, pain, or judgement from your church community. Essentially, you are just unable to “find your place”. This is prevalent in the Christian community, but can be extended to other religions.
Now that I am an adult I am beginning to heal from the churchhurt that was inflicted on me as a child.