1. Healing Usagi, then he is not a Mafia member. and Mafia members are losers
2. Blocking the town.
3. Guarding Kino Makoto.
4. Guarding Aino Minako.
5. Killing Mafia members
It doesn't look like guarding; it's either a block or healing. Most likely, it's a block. Then, the lizard has 2 peaceful roles or a Mafia role, considering that Aino Minako blocked the guard.
UPD: the Mafia is either blocking or using natural defense.