Gay Romance tag is the MDL and western equivalent of BL. It is used only when the story is a Romance story and the main characters are gay. Tag description, "A sub-genre of Romance that primarily focuses on two or more main male characters falling in love and possibly ending up in a homosexual or homoromantic relationship."
If we could a synonym to it, we would add BL, but for now, we can't. But the Gay Romance tag should serve the same exact role, even if we don't add BL.
Tags (Same for the lesbian tag):
LGBTQ+: A material depicting lesbian, gay, bisexual, transgender and queer (or questioning), and others.
Gay Character: The depiction of a character that is sexually or romantically attracted to people of one's own sex.
Gay Relationship (Use only when marked as a Spoiler if they are not dating in the beginning): Focuses on two or more main male characters already dating or ending up together in a romantic or sexual relationship.
Gay Romance: A sub-genre of Romance that primarily focuses on two or more main male characters falling in love and possibly ending up in a homosexual or homoromantic relationship."