The Brief: "Cape For" means someone is defending another individual or going out of their way to "save" them. It typically has a negative connotation.

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“Cape for” is a phrase used as part of a larger sentence to indicate someone is defending another individual or going out of their way to “save” someone. It typically has a negative connotation.
“Cape for” refers to a superhero’s cape.
While “caping” has been around for years (earliest Urban Dictionary reference is 2015), the term “cape for” has risen in popularity on Twitter in early June 2020. Twitter users typically uses the phrase to call out someone who is not worthy of “saving.”
These are your "sOnZ" y'all are telling me to collectively cape for? He said he's only obligated to protect his wife but when I tell BW to only support BM they know personally, I "hAtE bM" 🤔? https://t.co/QhkVRQpp5Z
— Paris Milan (@ParisMilanYT) June 8, 2020