The universe just loves bending backwards to screw with yukkuri.
Maybe the dog recognised that the tombstone (tombstick more like) was some sort of monument. Like how dogs prefer to pee next to lampposts rather than in the middle of the street.
Yuyun!YuchiHn...!PoingPoingYuchichiTrudge...Trudge...Sniff sniffSniff sniffYu!?Yuu...!Yu...Pyapya! Myamya! And widdwe shish!CHAGE ID EAJYYupi...Yugu...!