He sounds kind of like the German version of Mervin Tran.
Yes, fourth. The first was Annabelle Proelss, but she grew a lot in the puberty and became a bit big for him. Then Ruben teamed up with Mary Vartmann. After splitting with her he told that there was so great difference in their personalities and tempers that he knew that partnership would last a season, maybe two, not more. Then his partner became Annika Hocke. They had a successful Olympics season and having had some difficulties in last postolympics season they ended their partnership.