Let's talk about Aspec characters and relationships!
I'm aroace. I write a lot of characters who are aspec in some way. I have a lot of aspec friends. And this is why your aspec character is driving me crazy. There's also sex talk in here so if you're not mature enough to handle it please scroll past.
Edit: Allos also should reblog this if you found it helpful.
First lets get some terms right:
Aromantic (aro) and Asexual (ace) are two distinct things. Aroace means you're both aromantic and asexual at the same time. It is generally referred to as 'aspec' (aro/ace spectrum) when you fall on one or both spectrums. If you are not aspec you are allosexual/alloromantic (allo). It just means someone who isn't ace or aro. You can also be aroallo or aceallo (aromantic allosexual, asexual alloromantic). All these terms are neutral and not used in derogatory ways similar to trans/cis. It's a descriptive word not a put down.
Now about those characters and their relationships. Because that is the most :))))) to me as an aroace is when people just don't know how to handle an aspec character. Usually because they're allo. But that's okay you probably don't know and we're all here to learn from each other. Here's some things to consider when you want to make or write an aspec person.
Ace's do sometimes have sex. They just aren't motivated by sex. That's it.
Along with sex your ace character may also masturbate and feel good being touched. They also might only like touching themselves and hate when other people do it. They usually also know when someone is hot/sexy and will comment on it. Finding someone sexy =/= we want to fuck them. Thinking someone is hot =/= we want to fuck them. We're still human. We know what a hot human looks like. Your ace character might be attracted to someone's appearance aesthetically but have no interest in their bits. Your ace character might fall in love with the most beautiful person in your story and never show any interest of wanting to bed them.
They can have boyfriends/girlfriends/romantic partners they do or don't have sex with. But they can be anywhere on the spectrum of sex repulsive, to sex positive, to absolute sex hound. Some of the horniest people you know are probably ace. Some of the horniest people I know are ace, and I have a lot of ace friends.
And we're not all virgins. Some ace's had sex and realized 'nah fam. Didn't do it for me' and never did it again. Others are virgins and have no intention ever of having sex. Others are virgins but don't care either way? It just hasn't happened. Others enjoy sex with their partners. Some are parents! You can be ace and had enough sex to procreate. Some also think sex is icky or it squicks them out. Some might be squicked out at the thought of sex with another person but they're fine looking at porn or doing it themselves. There is a wide range of what asexuals are into just like allos.
Aros also sometimes do the sex. They are not motivated by romance. That's it.
That being said your aro character can have a boyfriend/girlfriend/partner and it can be 'romantic'. It doesn't have to be a queer platonic relationship. Your aro character also might not want to be in a relationship at all. It is not weird for your aro character to call their partner their partner or bf/gf or if they're married their husband/wife.
Aro people do not get butterflies. They don't really get flustered around people they like. There's no spark. And they don't feel that romantic attraction allos do when they meet someone and fall in love with them. I've found that aro people are also terrible at flirting or picking up flirting cues. At least in my own personal experience when it took my aro ass 3 years to realize some girl was flirting with me and I just thought she was being nice to me. Take the 'useless lesbian' trope and take it to 11. We just don't know. Aro people also know when other people are hot. Just like aces just because we're aro doesn't mean we don't know a baddy when we see one. We just probably won't realize said baddy is flirting with us...
Aro character still love. They love their family, they love their friends, they love their partners. And it's all real love. The love is still there. Aro characters also probably know what they should do to mimic being in love. Even if we don't love someone more than platonically they may still do the things romantic partners do with their partner. Some don't! And that's fine too. Sometimes you're boyfriends and you share the same bed with him, and sometimes your girlfriend is just your roommate. Both are totally valid aro relationships. Maybe your character kisses their partner passionately and they like it, or they might only kiss during sex, or they might not kiss on the mouth. All valid and correct, still no romo. Kissing =/= romance for aros. Sex =/=romance for aros.
Aroace characters do all those things! At once! They can do the sex, and the boyfriend/girlfriend/partner and loving their friends. They just are not motivated by sex or romance. Kissing =/= sexual attraction. Sex =/= romantic love.
Being aspec is looking at the most beautiful and delicious cake in the world and going 'neat, cake' and walking away not even wondering what it tastes like, not even for a second considering having a bite. It's a cake. Neat. You are not motivated by cake. You don't even really care about cake. It's nice that other people fucking loooooooove cake but it's just not for you.
We also know what love is supposed to be like, what a 'healthy sexual' relationship should feel like. It's everywhere. All around us. Constantly. It's also sometimes fucking exhausting! It's why some aspec people can be a bit agro. We get it you're in love/got a new partner/are sleeping with someone/really sexually attracted to this person/keep spamming us with your celeb thirst pics/etc. It does get tiring sometimes. We don't care about the cake and sometimes listening to you talk about the cake drives us crazy. Consider that too when writing aspec characters. Sometimes their friends and their cakes are annoying no matter how much they love them platonically or romantically.
Anyway just some things to consider for your aspec OCs from an older aroace. Should be said aspec is a wide spectrum and I'm drawing on my own experience as an aroace with aspec friends, and my writing of those characters. If you have more questions about writing characters on this spectrum feel free to ask!