If the situation wants it, because you both have to shower, but only have the time for one. Expect a rainy day, one of your friends has his/her birthday party, so you and your other friend wanted to buy a gift. While coming back to your house you got very wet, but the party starts in another hour or something. Would you do it together? And when not:
2. what's with a stranger?
Its more common to shower with someone of the own gender,in sport clubs or spas for example.
If you would know one of them would be homosexual, would it be a problem for you to shower with him/her?
Both in a 'normal' way, so no touching or something.
(I hope it is no problem to ask it in behavior , I didn't know where to do it. I decided to do it in sexuality, but I wasn't able to because of my level -.-)
For the second part: Of course its not common to have the same gender in the shower you are in. Sport clubs are different from the first scenario, so just ignore this, please.