A teen on Reddit says his "racist" older sister doesn't want her boyfriend to propose to her because he's Asian and she won't ever marry him.

"She found a boyfriend (let’s call him Alex) when she was 25 and he was 27 and overall he’s a really cool guy ... He makes a good amount of money and occasionally spoils me and my sister with gifts, fancy meals, the works," he wrote via Reddit, adding that Alex is "attractive," works out daily at the gym and has a stable job.

When Alex asked the teen for his permission to propose to his sister, Mary, the boy floated the idea to his sister.

"When I asked Mary how she would have felt if he happened to propose, she didn’t seem excited at all. If anything, she was like, 'Oh… that would be cool.' I asked her if she didn’t wanna get married yet and she said she did… just not to him. WHICH DIDN'T MAKE SENSE TO ME," he wrote.

"He genuinely cares about her feelings, even has a routine for her period weeks. I’d date him if I swung that way, honestly. That’s when she told me she loves him as a person, but wouldn’t want to marry him because HE IS ASIAN," he continued.

READ MORE: Woman Says Boyfriend’s K-Pop-Loving Little Sister Is ‘Racist'

When he asked his sister why she doesn't just "break up with him" if she's not interested in a future together, she said she enjoys the "expensive stuff" he buys her.

"I told her she was racist and only with him to leech off his ... money and she got offended (the whole 'I’m not racist I have [x] friends' argument). I told Mary to either tell him the truth, or I would," he wrote.

Now, his sister isn't speaking to him, and he's been hanging out more with Alex, who asked him "to go ring shopping in April so he can propose after I graduate in May."

The teen is wondering if he should tell Alex, because he doesn't want to see him get "used and abused." At the same time, he doesn't want to ruin his relationship with his "one and only sister."

In the comments sections, Reddit users mostly supported the teen's instinct to tell  the boyfriend the truth.

"Please, please tell him before he gets married to your racist sister who’s just using him for his money. That poor man being strung along for [three] years," one person wrote.

"It's FAR better for him to get hurt now, rather than getting married to someone who doesn't love him and have an unhappy marriage before a divorce down the road," another commented.

"I think the right thing to do would be to tell your sister he is planning to propose and to end it now vs. telling him. Let her end the relationship instead of the other way. When he figures out, he's going to leave and you're not going to be friends with him anymore. You will still be the brother to your sister. She's in the wrong 1000%, but when a good friend/family member is wrong you tell them that and help them make the right decision. Otherwise, she won't trust you enough to confide in you anymore and you'll sever that relationship. Bad long term outcome right there," someone else advised.

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