kobo sage

Hi,

when I plug in my kobo sage e-reader I get this in dmesg (amd64, -current-ish):

umass0 at uhub0 port 3 configuration 1 interface 0 "Linux 4.9.56 with sunxi_usb_udc Composite Gadget (ACM + MS)" rev 2.00/4.09 addr 3
umass0: using SCSI over Bulk-Only
scsibus4 at umass0: 2 targets, initiator 0

My previous e-reader (kobo aura hd iirc) would put something similar
into dmesg, but there would also be a line about sd(4) and I could mount
(in my case) /dev/sd2i as msdos file system.

How do I access the kobo sage from OpenBSD and to put stuff on?

Thanks,
Florian

--
In my defence, I have been left unsupervised.