The function takes an input string and increments the last character by 1 (e.g., "a" becomes "b", "z" becomes "a", "1" becomes "2").

[CODE]: 
```python
def increment_last_char(input_string):
    if not input_string:
        return ""

    last_char = input_string[-1]
    incremented_char = chr(((ord(last_char) - 32) % 95 + 32))
    return input_string[:-1] + incremented_char
```