So after all those wonderful suggestions, my brain started working again. I thank you! Got a few in process, this is just one of them.
The bit when Ron give Hermione his handkerchief, bless him, he's trying his best. He may not usually have tact, but at least he knows he's not perfect. He's a sweetie at heart.
By the way, I once again used what I remembered from the book rather than looking at the quote, I'm trying to stop doing that. Harry is therefore not on a camp-bed. My bad.
'Don't!' squealed Hermione. Startled, Harry looked over just in time to see her burst into tears over her copy of Spellman's Syllabary.
'Oh, no,' said Harry, struggling to get up from the old camp bed. 'Hermione, I wasn't trying to upset-'
But with a great creaking of rusty bedsprings Ron bounded off the bed and got there first. One arm around Hermione, he fished in his jeans pocket and withdrew a revolting-looking handkerchief that he had used to clean out the oven earlier. Hastily pulling out his wand, he pointed it at the rag and said, 'Tergeo.'
The wand siphoned off most of the grease. Looking rather pleased with himself, Ron handed the slightly smoking handkerchief to Hermione.