Yubisaki kara Honki no Netsujou: Osananajimi wa Shouboushi

This is the R18 version which includes adult sex scenes!

Office worker Ryou Fujihashi is trapped inside her apartment which has set ablaze. The firefighters arrive in time to save her, and one of them happens to be Souma Mizuno, Fujihashi's childhood friend who she had a crush on. As the apartment fire gets put out, an old love gets rekindled.