fluff
1. It's the day of (character 1) and (character 2)'s wedding, but (character 1 is starting to feel nervous.

2. soulmate au- people have there soul mates names written on there arms.

3. (Character 1) takes (character 2) to a bar.

4. (Character 1) is moving in with (character 2).

angst
1.The zombie apocalypse has come and (charecter 1) is looking for (character 2) when they find themselves being chased by (sibling/friend). (Thank you Lynxtail_807 for your zombie au idea).

2. (Charecter 1) has been a little unwell recently so (charecter 2) goes to look after them, unfortunately it looks like (charecter 1) is getting worse...

3.war has broken out, and (character 1) must decide weather they fight with (character 2) or (sibling/friend).

Mpreg/normal pregnancy

1. (Character 1) has discovered they are pregnant, but in past conversations they know (character 2) doesn't want kids yet.

2. (Character 1) and (character 2) have been trying for a baby for a while and are finally expecting.

3. (Character 1) is going into labour.