no, if I'm not into someone I make sure they know
Ive had my heart played with, so no, it is not right if you have no intention of being with him, only flirt if you feel you may have a future with the person, otherwise your just destructing things
If someone knows that someone cares for them, it's cruel to knowingly tease. However, sometimes being kind and friendly can be misconstrued. Some people are naturally flirty. Some people are naturally warm. It isn't always intentional, but that's not to say that it never happens. Unfortunately, some people just like to play games.
No, that's cruel and repulsive.
Love can never correctly be used as a condition.