A toner comprising a toner particle comprising a core particle comprising a binder resin, and a shell on a surface of the core particle, wherein the shell comprises an oxazoline group and a polyvalent metal, and in an electron image of a cross-section of the toner particle taken with a transmission electron microscope, the polyvalent metal has atomic concentration C(M) of 0.0010 to 0.5000 atomic % as measured by energy dispersive X-ray analysis of the shell.