I know a zillion ways to refer to how people are homosexual, but I just realized I'm not sure of any common ways to refer to someone being straight. All I've heard and know is basically how to say one is "not homosexual".
If possible, I'd like the most casual/common term used.
Edit: From this jdrama I'm watching, I'm inclined to believe that heterosexuality is so normalized, that there's no common way to refer to it outside of the formal 異性愛者｛いせいあいしゃ｝. Just like how, in English, there's a zillion words for handicapped people, but no common words for people without any handicaps. (e.g. "paraplegic" for not having functioning legs, but no word for having functioning legs, because having functioning legs is just so normalized)