Found, link in comments
Not sure where I read this, and I think it was a WIP--or else I got interrupted before I finished the story--but Harry, who is staying at Grimauld Place, decides to bribe Snape into telling him what the Order is up to by offering up himself for sex. Harry, who had been a virgin, decides that sex with Snape is quite pleasant, and the man is after all, bearable. He realizes the trouble Snape would be in if their relationship becomes public, and decides since he never expects to have a normal loving relationship that this one based on growing respect is pretty good, and that in order to protect Snape from accusations of having taken advantage of him, he will formalize/legalize their growing relationship by publicly choosing Snape as his partner.
Meanwhile, and I won't guarantee this is the same story, but I think it is, Hermione, who had been closing up her parents' house, had been rescued from a mugging/rape scenario by Lucius Malfoy, who is searching for a new spouse. To gain political legitimacy, he has decided his new spouse should be muggleborn. He claims Hermione's agreement to marry him as the price to discharge the life-debt she owes him for saving her from the attackers. Of course when Ron & other Weasleys see the public announcement that she is engaged to Lucius, they freak out. I don't know if Harry's new relationship had been made public yet, but I think he and Hermione had met to discuss their situations and commiserate about no-one understanding their choices, and perhaps Harry had planned new legislation to introduce...I think one reason he had been so desperate to get info on the Order's doings is that he was now of age, or emancipated, so he could claim his seats in the Wizamagot(sp?).
Meanwhile, and I won't guarantee this is the same story, but I think it is, Hermione, who had been closing up her parents' house, had been rescued from a mugging/rape scenario by Lucius Malfoy, who is searching for a new spouse. To gain political legitimacy, he has decided his new spouse should be muggleborn. He claims Hermione's agreement to marry him as the price to discharge the life-debt she owes him for saving her from the attackers. Of course when Ron & other Weasleys see the public announcement that she is engaged to Lucius, they freak out. I don't know if Harry's new relationship had been made public yet, but I think he and Hermione had met to discuss their situations and commiserate about no-one understanding their choices, and perhaps Harry had planned new legislation to introduce...I think one reason he had been so desperate to get info on the Order's doings is that he was now of age, or emancipated, so he could claim his seats in the Wizamagot(sp?).