Pet toilet system

A pet toilet system comprising:

• an excretion container, having a liquid-permeable bottom surface portion, that accommodates toilet sand;
• a tray, disposed below the excretion container, that accommodates an absorption sheet that absorbs liquid permeated through the liquid-permeable bottom surface portion;
• a lower container that holds the tray;
• and
• an upper container, disposed above the excretion container, having:
• a front wall portion having an enter/exit portion through which a pet enters and exits;
• a pair of side wall portions, facing each other in a width direction of the enter/exit portion, extending in a front-rear direction of the upper container;
• and
• a rear wall portion facing the enter/exit portion in the front-rear direction, wherein
• the upper container includes an opening region having an opening portion above the liquid-permeable bottom surface portion,
• the opening portion has a slit shape,
• the upper container further has an outer extension portion, disposed on a wall portion including the opening region, extending outward from the wall portion, and
• the outer extension portion has a guide groove along an extending direction of the outer extension portion.

A pet toilet system comprising:

• an excretion container, having a liquid-permeable bottom surface portion, that accommodates toilet sand;
• a tray, disposed below the excretion container, that accommodates an absorption sheet that absorbs liquid permeated through the liquid-permeable bottom surface portion;
• a lower container that holds the tray;
• and
• an upper container, disposed above the excretion container, having:
• a front wall portion having an enter/exit portion through which a pet enters and exits;
• a pair of side wall portions, facing each other in a width direction of the enter/exit portion, extending in a front-rear direction of the upper container;
• and
• a rear wall portion facing the enter/exit portion in the front-rear direction, wherein
• the upper container includes an opening region having an opening portion above the liquid-permeable bottom surface portion,
• the opening portion has a slit shape,
• the pet toilet system further comprises an external additive member, disposed outside the opening region, facing the opening region, and
• a surface of the external additive member has cover openings at predetermined intervals in a vertical direction of the pet toilet system.