I think the katakana used are "ダンナミエ" which would be "dannamie" but I'm not sure since it doesn't make any sense to me.
Black Star always address Shinigami-sama as 旦那 (danna), which is more or less the equivalent of "Boss" or "Sir."
Black Star is an idiot so he uses the kana (because he doesn't know the kanji) and the wrong kanji when addressing his autograph to Shinigami-sama. Here he means to say 旦那へ, which is essentially "To Boss." For some inexplicable reason, he uses 江 ("e" in this case). へ is pronounced え (e) in modern Japanese when indicating a direction (I.e. addressing something to someone). In other words, what he writes is the equivalent of someone writing "Two BOSS" on an autograph.
The katakana ダンナ appear to mean something like "husband". Though it has a kanji form (旦那), I've found a few instances on twitter where the katakana is used to mean the same thing: husband.
The kanji, 江, means "bay" or "river" and can also be a name, but I'm not sure how it fits with the katakana of "danna". I'm still learning Japanese and I'm fairly sure it means the same thing in Japanese as it does Chinese. Will edit if/when I find a better answer.