Koibito Ijou no Koto wo, Kanojo ja Nai Kimi to.

Fuyu is exhausted from the unrelenting criticism and the unreasonable workload from his boss... Until one day, when he runs into Ito, his ex-girlfriend from college. Fuyu is so happy to see Ito that he immediately invites her out for a drink, and they talked about their old days and new lives. Just as he was thinking that this is a nice kind of friendship, they stumble into a one-night stand... (Source: Ura Sunday, translated)