Introducing: Luckeon! (Ghost-Type Evolution)
Okay, so, this is kinda a farfetched idea, but I ran with it for fun. I recently read Rime of the Ancient Mariner by Coleridge. In this poem, an old Mariner and his crew become entrapped by ice on an expedition to Antarctica. When all hope seems lost, an albatross comes along and becomes (essentially) the "good luck charm" for the boat. The ice clears and the ship sails away. However, the Mariner ends up killing the albatross for reasons unknown.
From this point on, the Mariner is cursed. The winds stop blowing his ship, he can't find anything to drink, and his entire crew drops dead. Far along in the distance, the Mariner sees a ship with two ladies on it: one is Death, and the other Life-In-Death. Life-In-Death is shouting "I won! I won!". This shows that the Mariner was not to die, but simply pay a gargantuan penance during his lifetime.
So, basically, the concept of Life-In-Death and the "chance" of getting it comes through in Luckeon. Maybe Luckeon was an Eevee who Life-In-Death chose to be ridiculed, or maybe Luckeon evolves from the torture/sufffering of an Eevee.
The red and blue are supposed to look like colors associated with things of chance or trick, like gambling, jesters, or clowns. Luckeon is like a sad, yet somewhat evil pantomime.
A Pokedex entry would be:
Luckeon wanders the streets of cities without ambition for much. Just as chance itself turns people away, many consider Luckeon to be an evil omen.