```json
{
  "no": ["no"],
  "yes": ["yes"]
}
```

Based on the provided information, the feature "has personal loan?" is a categorical variable with two possible values: "no" and "yes". 

When the target class is "no" (the client does not subscribe to a term deposit), the only possible value for the feature "loan" is "no".

When the target class is "yes" (the client does subscribe to a term deposit), the only possible value for the feature "loan" is "yes".

Therefore, in both cases, the lists of possible values for the feature "loan" are ["no"] and ["yes"] respectively.