I believe both type of people might enjoy this. Regardless of their own orientation many people are accepting of the same sex pairing and can enjoy a good story, good characters, etc.
There is no reason not to watch something that includes gay characters as a straight person. It doesn't make you gay if you enjoy romance between gay characters. I know many straight people who have enjoyed these kinds of anime in the past.
Straight people do enjoy them like me. I am straight may be bi is the correct word. I like men and women alike. I don't see what's wrong with enjoying plot