While you have another "Madolche" monster on the field, use this card's effect by targeting itself; its decent defense will allow it to last for a while, and you won't have to worry about denying one of your other monsters an attack.
You could also use this effect to target 1 "Madolche" monster that has already attacked, and you wish to change it to Defense Position for protection; when targeting an opponent's monster, target 1 that has a low/lower DEF than its ATK.
This card works very well with "Madolche Puddingcess". Not only its high DEF will protect this card, giving you an easy Tribute for "Puddingcess", but shifting a monster to Defense Position also means that "Puddingcess" will survive if she attacks that monster and destroy a card via her effect.
Special Summon this card with "Madolche Mewfeuille", then activate his effect to change a monster your opponent controls to Defense Position. Then, Xyz Summon "Soul of Silvermountain". Since he has low ATK, shifting a monster to Defense Position makes it much easier to activate his effect.