Please help me find this manga!

Hello everyone, I once read a really good (and smutty) manga on here before I made an account so I didn't it to any list. But now I've been trying to find it anywhere and I just can't! It's a story about a man who has to marry another man (a foreigner) to save his father's company. They strike up some kind of deal (I think it went like this: If you don't want to have sex with me by the end of the month you don't have to marry me?) and then it just turns straight filthy. Everyday they do foreplay until the uke gives in and wants sex so they end up together. But it turns out the seme was actually in love with him because they meet when they were younger, and the seme also has a really huge penis I believe. It had some kind of obscene name but I thought it was hilarious, and of course I can't remember it. It came out sometime in 2016.
Well, I hope this is enough information. Can you guys help me out?