ηηΊγͺγ η΄ ι逨ηηΊ η΄ ι逨ηηΊγͺγ³γ―
"Explosion gag", "SDM explodes", "Hyperlink: SDM Explodes"
"Now that's a real Touhou (/Kancolle/AzLane/Granblue/GFL/Genshin/etc.) manga!"
When an explosion is used to provide a literally explosive punchline for comedy purposes.
This often involves the SDM.