Student council has said to the girls that their club must present a project related to the refugee's cause. So Yui thought it would be a nice idea to interview some African guys who have just arrived in Japan and even try to help integrate these guys into the new country... What she didn't know was that they were far more interested in integrating their DNA with her's!
So nice of them to think about the next generation first of all...
Their yuri is laid-back indeed. But their interracial surely isn't.