Lover-In-Law (2008) Adult Anime Review

Tsutomu's parents passed away several years ago, before that they ran a flower shop. Now it's run by his older brother's wife, Mai, and he is living with them while attending the local college. When Tsutomu's brother gets transferred to another city, Mai is left alone and the only person around to help out is Tsutomu. Due to this fact, Mai is starting to feel that certain needs are very unfulfilled. Tsutomu realizes this and his feelings for Mai begin to surface. While all of this is going on, Kozue, Mai's friend and senpai from school just happens to be hired to help out around the store. Almost immediately, Kozue has notices that Tsutomu and Mai have a relationship that’s a little more that brother & sister-in-law. This strikes Kozue hard, since she is also very lonely herself, because her husband is rarely home.