2-TTIRAAS
The 10 Demon Lords or just the other demon lord of the Octogram for some reason decide to make a bet or something to see who can become Rimuru's spouse/consort.
How did it start? Probably someone making a comment about how Rimuru looked like the perfect wife or how beautiful he was which got away as many things do when in the demon lords hands.
They all tried their best, from outright flirting or saying they want to marry Rimuru to giving subtle hints or courting offerings, but for some reason Rimuru seemed oblivious to it or didn't actually understand their intentions.
At first they assumed that it was because he must be pure so he didn't know anything about romance or even sex but it wasn't as they visited Tempest one time that they realized that Tempest had their own ways of courting.
Tempest courting ways were a mixture of many different ones as it takes in account the different races living there as well as things Rimuru knew from his times as Satoru.
First there was the part of giving a gift to the person they intended to court but it couldn't be just anything, it must be something important or essential to the one who is courting as a way to show they trust their intended with something so important(an example was Kurobe gifting Haruna his most precious and used weapon making object).
Second the person being courted after being given the gift must give their answer to the one courting them, it can be wrapped rice or a handkerchief(it depends of the person being courted knowing or not how to cook) with them having their own ways to signify their answers: if the wrapped rice has two red chopsticks it means they accept the courtship, it it has pine needles it means the person is unsure so the one courting may continue but they may still get rejected, if it has only one chopstick it means you have been rejected and in the case of handkerchiefs if it is a scented(perfumed) one it means your courting is accepted, if it has no scent it means they are unsure and if it is a damaged one then you have been rejected(some examples are Benimaru giving his now wives wrapped rice with pine needles and Souei giving Souka a damaged handkerchief)
And the third part came to be when someone is being courted by more then one person, the ones courting said person will either fight to decide who will be the first spouse or for the courted one to make a decision on the one they want to marry based on what they see in the fight but it can also be used the method of the ones courting the same person building a house/making something for the one they are courting and the one the courted likes more will be their spouse or first spouse...of course that there are some people that decide to sit and have tea as they discussion what to do and come to a decision like that(an example being Benimaru having courted Souei and be courted by Momiji and Albis which lead for the trio to fight to choose who would be Benimaru's first spouse with Souei winning while the other two talked and decided to share the position of second spouse together).
Of course that finding this, the demon lords thought that they know had their chance by using Tempest courting methods on Rimuru but before they could try to do that, Milim(or all of them depending the timeline used) received an invitation to Rimuru's wedding with someone(it can be anyone you prefer but I had in mind one of these people: Veldora, Masayuki, Haruna or Eren)
It is a stupid idea but it might be an amusing one especially if it is used as a 5+1(like the attempts of the Demon Lords at getting with Rimuru and then the +1 being them founding about Tempest courting method and Rimuru's future marriage).
