Maybe hard to tell in this picture, but IRL it looks...not recent.
Who wrote it?
Did they live there?
Maybe the bricklayer?
Who was it for?*
Or maybe someone just loves bricks?
Is it from the 90's? The 1890's?
WHO CAN KNOW!
Maybe 100 years ago, this part was covered in plaster, and it was secret for a really long time?*
Why haven't I noticed it before now?
Why hasn't anyone noticed this before now?
(And, most important/probable) do I have a house-ghost trying to send me a ghost valentine?*