Twinpea
A combination of 'twin' and 'two peas in a pod'. This type of twin-bonding is stronger than that of the ordinary twin. Nothing can come between two twinpeas, and they are alike in every single way- they have zero differences!
Today, my twinpea and I said the same sentance at the same time- there's no one who can read my mind better than my twinpea!