Well to a lot of people it means the best of both worlds like someone who is married and they are cheating on their spouse--they have their cake--the spouse dose not know-- and they are eating it to-- the one they are with and not suppose to be--get it.
Just be nice to him and see how he reacts to you starting out as friends is comfortable and then you can find out all you need for the answer to your own question
As soon as it is conceived it is a life even though a lot of people do not think so -- think about this when you were conceived what if your parents aborted you as soon as they found out then you would not exist