It's a lovely piece of work done by an SS/HG artist named usagistu. She does art of Severus and Hermione (as an adult! not student Hermione) and she's very good. I'm a huge fan of SS/HG where Hermione is 18 or older (which technically does include AU stories of 7th year!Hermione). According to canon, she technically turns 18 in September of her 7th year.