to determine love interests and love life, you need to determine their sexuality! here's a list of sexualities that i know of and if there are more then please add them in the comments! however i will not be adding in terms such as 'draco / dreamsexual' because that's mocking the lgbtqiap+ community.

a) straight ( attraction towards opposite gender )
b) aromantic + asexual ( no romantic or sexual feelings )
c) biromantic + bisexual ( attracted to two genders, including their own )
d) demiromantic + demisexual ( having attraction only after establishing a strong bond )
e) gay / lesbian ( attraction to only their gender ) 
f) graysexual + grayromantic ( experiencing limited romantic or sexual desire )
g) pansexual + panromantic ( completely genderblind in attraction to all genders )
h) omniromantic + omnisexual ( attracted to all genders, but has a preference )
i) poly ( attraction to multiple people at once ) 
j) sapiosexual ( attraction based on iq and eq, not looks )
k) ceterosexual / skoliosexual (?) ( attraction to those who are not cis )

your oc can also be a combination! for example : : 
1. biromantic asexual

2. heteromantic pansexual

3. sapioromantic demisexual
e t c . . .