Devices, systems, and methods for delivering a substance within a mammalian luminal organ or area adjacent thereto. In at least one exemplary embodiment of a system of the present disclosure, the system comprises an inner delivery device, comprising an inner portion configured to receive a substance therein, a pock tip at or near a distal end of the inner delivery device, the pock tip configured to deliver the substance from the inner portion, through a pock tip aperture defined within the pock tip, and into a mammalian tissue and/or luminal organ, and an embolus positioned within the inner portion, the embolus configured so that the substance remains distal to the embolus when the substance is positioned within the inner portion. In another embodiment, the system further comprises an outer catheter, comprising an elongate body, a guidewire lumen defined within the elongate body and configured to receive at least part of a guidewire therein, and a central lumen defined within the elongate body, the central lumen configured to receive at least a portion of the inner delivery device.
