Love Triangle has these relationships to other tropes:

parents kids shares a parent with:
Love Interests
Betty And Veronica
Love Dodecahedron
Murder The Hypotenuse
Romantic False Lead
Sibling Triangle
Triang Relations
Two Person Love Triangle
Yandere Love Triangle
parent child
Love InterestsLittle Sister Heroine
''All Girls Want Bad Boys
''All Guys Want Cheerleaders
''Beta Couple
''Cake Eater
''Disposable Love Interest
''First Love
''Girl Of The Week
''Implied Love Interest
''Loves My Alter Ego
''Lust Object
''Official Couple
''Master Of The Mixed Message
''Relationship Sue
''Replacement Love Interest
''Second Love
''Settled For Gay
''Single Woman Seeks Good Man
''Student Teacher Romance
''Temporary Love Interest
''The Obstructive Love Interest
''Third Option Love Interest
''Unwanted Harem
''Unwanted Spouse
''Old Flame
''Damsel In Distress
''Satellite Love Interest
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