"When you see it, you'll shit bricks."
The Japanese equivalent on Pixiv is "おわかりいただけただろうか" or "お分かりいただけただろうか" (Owakari Itadaketa darou ka, 'Do you understand now?'). This phrase is from a horror TV show, "ほんとにあった! 呪いのビデオ" (Honto ni Atta! Noroi no Video, 'Cursed Videotapes Really Exist!'). When the TV staff replayed ghost videotapes sent by audiences, the phrase was used.