Well, it's a really awkward situation. If it was an innocent accident, like your friend was changing in the wrong place by mistake. You should apologize to your wife on behalf of your friend and make it clear that it won't happen again. And also, encourage your friend to keep his modesty around your family in the future.
This is a very awkward situation. First, you should talk to your friend privately. Make it clear that it was an accident but also express your discomfort. For example, you could say 'I know it was an accident, but it made me and my wife feel really uncomfortable.' Then, make sure your friend respects your family's privacy in the future.
Acknowledge the awkwardness right away. Say something like 'This is so embarrassing, but it was an accident.' Try to make a light - hearted joke if appropriate, but be careful not to seem like you're not taking it seriously. Then quickly move on to another topic or activity to shift the focus.
The first reaction would be to shield my body. Then I'd say something like 'I'm so sorry, I didn't know you were coming.' I'd also try to gauge her reaction. If she seems really uncomfortable, I might give her some space for a while. But if she's more laid - back about it, we could probably just laugh it off and pretend it didn't happen. However, it's still a very awkward situation that I'd rather not be in.
If a wife sees her friend's large collection of books, she might be really impressed. She could start looking through the collection, finding some rare titles. It might inspire her to start her own collection or read more.
Just be straightforward and say you're very sorry for the accidental sight. Keep it simple and sincere, like 'I'm so sorry for what just happened. It was completely accidental.'
One possible reason could be a lack of privacy in the living environment. For example, if you live in a shared accommodation and there was a mistake with the bathroom or bedroom access. Another reason might be an unexpected situation during a trip or an event where there was a lack of proper facilities or communication. It could also be a case of misbehavior on the part of the friend, but that's a more serious and less likely scenario if your friend is trustworthy.
One possible reason could be a misunderstanding about who was in the house. Maybe she thought her friend had left already and she was in the privacy of her own home. Another reason could be a wardrobe malfunction, like a towel falling off suddenly if she was just out of the shower and didn't expect her friend to be around.