I got a feeling of immorality drawing this manga right in front of Sanae-san at a cafe! Naturally, as a manga, this is exaggerated! It must be! Masking tape sure burns well!
.."always watch where you're aiming the laser" is right up there with "don't stick your head in the machine" with safety tips around industrial machines that are designed to burn or cut things.
I think it is a reference to the M-1 manzai where Flandre had set the mansion on fire. It was a returning joke in other manzai as well.
It has been a recurring joke here on danbooru, that it's only a real Touhou doujin if the SDM explodes, because Bomber Grape once said you couldn't have one without the SDM exploding.