>>281445290
August 13th, 8-13 or 813
8 - Ha(chi)
1 - i(chi)
3 - Engrish "suri"
Ha-i-suri, twist the "ha" ハ into "pa" パ and the "su" ス into zu ズ, "pa-i-zuri".
You'll see this a lot from titty artists now and then, along with stuff like 11081 "ii oppai", which is also why we have "oppai day" (boobs day) on August 1st and "ii oppai day" (good boobs day) on November 8th.