To get these to work, follow the instructions as best as possible. Where it says get another character, use the instructions to get it.
The Kodo-Ten
Just treat it pretty well.
The Tako-Ten
Hatch at about 3.00pm, fill two hearts when it becomes a Maru-Ten, fill one heart at the beggining of next day.The should be a poop.
The Kuri-Ten
Get the Kodo-Ten and treat it pretty well.
The Puku-Ten
Get the Tako-Ten and treat it well.
The Oyaji-Chi
Get the Tako-Ten when it changes into the Tako-Ten treat it badly. Fill 1 heart when it becomes the Tako and then 1 the next day.
Twins
Get the Kuri-Ten and treat it well.
Onoto-Ten
Get the Oyaji-Chi, treat it well but keep it's deeds (praise) meter empty.