Тhe laws of yichud (Hebrew: איסור ייחוד issur yichud, prohibition of seclusion) is the prohibition of seclusion in a private area of a man and a woman who are not married to each other. Such seclusion is prohibited in order to prevent the two from being tempted or having the opportunity to commit adulterous or promiscuous acts.
Pesach Posuach – Open door. Yichud is alleviated when the door is open. This principle is known as pesach pasuach lireshus harabim, an open doorway to the public domain. The Shulchan Aruch rules: "If the door is open to the public domain, there is no concern of yichud." [...] Woman being secluded with another man is also justified when people outside can see through the window what is going on inside the house.