The Strosek series (「シュトロゼック」シリーズ "Shutorozekku" shirīzu) is the only series of Reactors that possess a humanoid form. This series and the Bible of Silver Cross have been created based on an Ancient Belkan tome (possibly the Book of Darkness), and Strosek's role is to connect and excite the three units, i.e. Driver, Divider, and Storage. As such, they are comparable to Unison Devices (which have their own Lord, weapon and storage tome).
The Strosek series is probably named after the obscure German car company Strosek Driving Design.
In-universe, individual Stroseks are named after flowers (e.g. Lily), as a joke of their original developer.