go inside the Building. theres 2 sqms you coudl take you takre the western one wait untill npc stands in the door. When the npc is inside the Dooryou mwall infront of you and close the door then you gna open the door and stand in it. Close the door again and be sure the 2 mwall spots behind you are still mwalled. You close the door and then your stacked with the npc. Check it out and see how perfect it is